Modern pigments and their vehicles;

MODERN PIGMENTS

AND THEIR

YEHICLES

THEIR PROPERTIES AND USES CON-
SIDERED MAINLY FROM THE
PRACTICAL SIDE

AND

HOW TO MAKE TINTS FROM THEM

BY

FREDERICK MAIRE

i \

EX-EDITOK OF "PAINTING AND DECORATING," AUTHOR

OF THE "MODERN WOOD FINISHER," THE

"MODERN GRAINER"

FIRST EDITION

FIRST THOUSAND

NEW YORK

JOHN WILEY & SONS
LONDON : CHAPMAN & HALL, LIMITED

1908

t

COPYKIOHT. 1907.
BY

FREDERICK MAIRE

Stanbope

H. OILSON COMPANY
BOSTON, U. 8. A.

PREFACE

IT is to be regretted that notwithstanding it is a matter
of prime importance that both dealers in painters' supplies
and users of the same — the painters and decorators —
should be well posted about the materials they handle, the
vast majority have but the faintest ideas concerning
the properties of pigments. One would naturally suppose
that dealers ought to know all about them, their values,
cost of production, qualities and defects. Without
such knowledge they cannot truthfully answer the
questions daily put to them. This ignorance has made
it possible for unscrupulous manufacturers to palm off
almost anything upon them. Every manufacturer and
dealer has been a law unto himself, each differing from
nearly everyone else in the trade. This lack of standards
was really due to the indifference caused by the lack of
knowledge on the part of both dealers and consumers.
It has enabled the unprincipled to fleece an unsuspecting
public out of millions of dollars.

Now that the public is being made fully aware of what
they buy in the way of food, and that the general govern-
ment and most of the states are working together in
enforcing laws which require manufacturers to state
upon labels placed upon packages an exact statement of
what they contain, it is to be hoped that the same pro-
tection will be extended to all other compounded material
in the paint line which is subject to adulteration.

The blame for adulteration does not rest upon the
shoulders of the manufacturers and dealers only. Igno-

iii

iv PREFACE

ranee of what constitutes the value of an article and a
desire on the part of consumers to obtain it at a cost
below what it is worth are also very strong factors —
possibly the main ones why goods are adulterated at all.
Manufacturers and dealers would not undertake to
manufacture or sell material for which there would be no
demand.

The Master Painters' Association has done some
excellent work in past years to open the eyes of painters,
and through its efforts in showing up the rottenness in the
paint trade existing at the time of its inception a great
change for the better has been brought about.

The trade journals, however, have done even more
real good by bringing this work of the association to the
knowledge of thousands of those painters who are not
members of the association and who otherwise would
never have heard of it. Thanks to this agitation which
has been going on for the past eighteen years, the paint
situation is in a much healthier condition to-day.
Standards of quality are being established, and it is
possible to obtain colors dry, ground in oil, Japan or
water, which are exactly what the label represents them
to be.

It is not within the scope of this little book to go into
the detective business nor to make a specialty of exposing
the tricks of trade. Its purpose is to give a brief and
concise history of all valuable pigments useful in paint-
ing — the main sources of their derivation and supply;
their properties and chief uses; their good qualities and
their defects will be pointed out and incidentally there
will be presented the best methods of detecting adultera-
tion.

While tons of literature have been issued by the trade
journals and in book form, very little has been written

PREFACE V

upon pigments, and most of that has been in short sketches
and merely as a side issue to the main subject matter of
the volumes containing them.

Some excellent books on pigments have been published
in England and Germany. These were written by
chemists and are of use to manufacturers in particular.
They mainly treat what may be called the scientific side,
the practical being only treated incidentally or ignored
entirely. Of this character are such admirable works as
Field's Chromatography. Its high cost, even if it treated
pigments more fully from the consumer's viewpoint,
would prevent its purchase by the bulk of those who
otherwise would be interested in it and no doubt procure it.

It is impossible in as small a volume as this to enter
into the chemistry of pigments nor into some of the intri-
cate details of manufacture and preparations for use,
except in the briefest manner that will give the reader
a fair idea of its composition. This is about all that
painters or dealers require to know of the chemical side of
pigments. Additional details would be of no importance,
and none outside a manufacturer of colors would be
interested in them. This manual is written for the men
who use or sell pigments and who mainly want to know
what they can expect of them.

The author has made use of the best that has been said
upon the subject matter in the past. He has consulted
some of the best authorities and had access to nearly
everything that has been published on pigments, many of
these books being now out of print. He was also very
fortunate in that for a few years he had the pleasure of
having intercourse almost daily with the late lamented Wm.
C. Wilson of Philadelphia, who at that time was probably
the best posted man on pigments in America. The
information thus obtained has been largely drawn upon.

vi PREFACE

This little book will be of value to the young man who
is starting out to learn the painter's trade. It will
teach him what he ought to know about paints and
what he will never learn from the average journeyman
who is usually reticent and may very likely not know
enough about pigments to answer a novice's queries.
It will be useful to many painters who have never had
an opportunity to study the matter of pigments, except
in a haphazard sort of a way — without system and with
much guess-work. As to the dealers, many of them are
druggists who have a fair knowledge of chemistry.
These will find the chemical details sufficient to give the
information that is wanted. Other dealers not so well
informed find also enough explanation to enable them
to know if they are buying the right goods or paying a
fair price.

It is probable that errors have crept in and will crop
out when this book comes out in print. Good care has
been taken that there be no glaring ones, but it is still
possible that some may inadvertently have been over-
looked. Be that as it may, infallibility is not claimed,
but the author has given out what he honestly thinks
is reliable. Such as it is, this little book is confidently
submitted to an indulgent public.

F. MAIRE. •

HAMILTON, ILLINOIS.
Aug. 30, 1907.

CONTENTS

CHAPTER I

PAGE

PREFACE .... hi

PRELIMINARIES

Definition of the word " pigment." — Some substances are real
pigments in water, but only so by courtesy in oil. — Synopsis
of the manner in which the subject matter is to be treated in
succeeding chapters.

CHAPTER II
WHITE PIGMENTS 8

Introduction. — White lead, history, chemistry, and manu-
facture. — Dutch process; stack method of corrosion, cylinder
method, sulphate of lead, sublimed lead. — Dahl process; prop-
erties and uses. — Blow pipe and other tests for impurities.

CHAPTER III
WHITE PIGMENTS (Continued) 32

Zinc white; its history and chemistry, its properties and uses.

CHAPTER IV
WHITE PIGMENTS (Continued) 40

Earth whites ; their general characteristics. — Whiting (car-
bonate of lime) ; properties and uses. — China clay (kaolin) ;
properties and uses. — Gypsum (sulphate of lime) ; properties
and uses. — Silicate earths; properties and uses. — Silver
white; properties and uses. — Baryta white (sulphate of
barium) ; properties and uses.

vii

viii CONTENTS

CHAPTER V

PAGE

YELLOW PIGMENTS 57

Ochers; history and early use made of them, methods of
mining and preparing for market, divided into two classes,
the silicious and aluminous, various characteristics, proper-
ties and uses of each. — Grinding colors in shops, no econo-
my therein. — American ochers; their properties and uses.
— Artificially made ochers.

CHAPTER VI
YELLOW PIGMENTS (Continued) 73

The chrome yellows ; their various tones. — Medium chrome
yellow, only the chromate of lead. — Canary and lemon chrome
yellows. — Baryta lemon chrome yellow ; characteristics, .
properties and uses. — Adulterations; how to detect them.

— Comparisons and the judging of values by the scale test. —
Full directions for making it. — Useful for many other colors.

CHAPTER VII
YELLOW PIGMENTS (Continued) 86

Gamboge; production, properties and uses. — Aureolin or cobalt
yellow; properties and uses. — Indian yellow; properties and
uses. — Naples yellow; production, properties and uses. —
Dutch pink, yellow lake, Italian pink, quercitron, etc.; pro-
perties and uses. — Cadmium yellow ; properties and uses. —
King's yellow or orpiment; properties and uses.

CHAPTER VIII

RED PIGMENTS 95

Vermilion. — Quick silver vermilion; its history, chemistry
and manufacture ; properties and uses, adulteration. — The
imitation or vermilion reds ; peculiarities, properties and uses.

— American vermilion; properties and uses.

CHAPTER IX
RED PIGMENTS (Continued} 106

Venetian red; history and manufacture, characteristics, proper-
ties and uses. — Indian reds; characteristics, properties and
uses. — Tuscan reds ; properties and uses. — Red oxide of iron ;
characteristics, properties and uses.

CONTENTS ix

CHAPTER X

PAGE

RED PIGMENTS (Continued.') 116

Red lead; its chemistry and manufacture, properties and
uses. — Lakes; what they are. — Alizarin and purpurin; their
uses in the manufacture of lakes. — Rose pink; properties and
uses. — Rose lake; properties and uses. — Madder lakes;
include all shades and varieties of red lakes made from alizarin
and purpurin, many sold under proprietary names. —
Indian lake; properties and uses. — Carmine and the cochineal
lakes; characteristics, properties and uses. — Red ochers; what
they are.

CHAPTER XI
GREEN PIGMENTS 129

Chrome greens; composition, properties and uses. — All greens
under proprietary names are chrome greens. — Green oxide of
chromium, true chrome green; properties and uses. — Cobalt
green or zinc green; preparation, properties and uses. — Viri-
dian; properties and uses.

CHAPTER XII
GREEN PIGMENTS (Continued) 139

Terre verte; properties and uses. — Verdigris; derivation, proper-
ties and uses. — Paris or emerald green; chemistry, properties
and uses. — Malachite; properties and uses. — Scheele's green;
properties and uses.

CHAPTER XIII
BLUE PIGMENTS 145

Ultramarine blue; history, character, properties and uses. —
Prussian blue; chemical constituents, preparation, properties
and uses. — Chinese (Prussian) soluble blue; properties and
uses.

CHAPTER XIV
BLUE PIGMENTS (Continued) 152

Cobalt blue; preparation, properties and uses. The artificially
prepared cobalt blue. — Cceruleum ; properties and uses. —
Chessylite; properties and uses. — Smalt; properties and uses.

x CONTENTS

CHAPTER XV

PAGE

BROWN PIGMENTS 156

Umbers. — Raw umber; characteristics, properties and uses. —
Burnt umber; properties and uses. — Siennas. — Raw sienna;
where obtained, preparation, properties and uses. — Burnt
sienna; properties and uses. — Vandyke brown; properties and
uses. — The metallic browns; provenance, properties and
uses. — Spanish brown; properties and uses.

CHAPTER XVI
BLACK PIGMENTS 170

Lamp black; characteristics, manufacture, properties and uses. —
Carbon or gas black; properties and uses. — Ivory black. —
Coach black. — Drop black. — One and the same ; preparation,
properties and uses. — Charcoal black or blue black ; properties
and uses. — Graphite or plumbago; properties and uses.

CHAPTER XVII
SYNONYMS 181

A table to facilitate the finding of pigments known under various
names.

CHAPTER XVIII
VEHICLES USED IN GRINDING PIGMENTS AND IN APPLYING THEM 189

What vehicles are. — Raw linseed oil. — What a drying oil is. —
What a fixed oil is. — The only ones of use for exposed paint-
ing. — The provenance of linseed oil ; its manufacture and
preparation for use. — How linseed oil dries ; its proper-
ties.— Boiled linseed oil; its properties. — Nitric acid and
other tests for impurities. — Poppyseed oil; characteristics,
properties and uses.

CHAPTER XIX
VEHICLES (Continued) 206

The volatile oils; what they are; their properties and uses
in paint vehicles. — Spirits of turpentine; how obtained; its
diuretic properties. — Naphtha and benzine; properties and
uses. — All volatile oils solvent of gum-resins used as such in
varnish making.

CONTENTS xi

CHAPTER XX

PAGE

VEHICLES (Continued) 211

Varnishes, japans and alcoholic shellac solutions. — Varnishes;
what they are; their properties and uses as binders and vehi-
cles. — Japans;' some confusion as to what they are; their use
as vehicles, driers, alcoholic shellac solutions; properties and

CHAPTER XXI

SUBSTANCES USED AS CORRECTIVES AND BINDERS 217

Waxes. — Beeswax used in encaustic painting in earliest civiliza-
tion. — The vegetable waxes. — The paraffin waxes.

CHAPTER XXII

SUBSTANCES USED TO BIND PIGMENTS IN CONNECTION WITH

VEHICLES 220

Glues; manufacture, properties and uses. — Gum arabic; prove-
nance, properties and uses. — Starch, dextrin, honey, sugar,
molasses and glycerine. — Their properties and uses.

CHAPTER XXIII

DRIERS AND SICCATIVES 229

Boiled linseed oil as a siccative; properties and uses. — The lead
oxides ; the oxides of manganese. — Acetate of lead. — Sulphate
of zinc. — Their action upon linseed oil and other fixed oils
considered.

CHAPTER XXIV
THE COMPOUNDING OF PIGMENTS ..." 235

Philosophy of color. — Rules to guide one in the compounding
of tints.

CHAPTER XXV

A LIST OF THE PRINCIPAL TINTS AND OF PIGMENTS REQUIRED

TO MAKE THEM 243

A few cautionary words followed by the list of tints.

F THE " \

UNIVERSITY )

OF /

MODERN PIGMENTS AND THEIR VEHICLES
THEIR PROPERTIES AND USES

CHAPTER I

PRELIMINARIES

IN subsequent chapters it is intended to take up a study
of the various pigments which are used in ordinary
painting, as well as those employed by decorators for
either distemper or oil painting; those used by coach
and car painters will also be reviewed. The whole field
will be covered, with possibly the exception of a few pig-
ments which have become obsolete, and which have been
replaced by better ones.

The vehicles which are used in the application of pig-
ments will also be noticed, as in some respects they are
really of more importance than the pigments themselves.
Binding substances and correctives will also be described,
and their character and uses noted.

The word " pigment " is applied to coloring substances
which, when mixed with suitable vehicles, form paints. It
means " color," the word " color " being used indifferently
to mean a compound of various pigments, or a pigment
which has been ground ready for use; the various pig-
ments put up in cans and found for sale at the supply
stores are commonly known by that name. No matter

1

2 MODERN PIGMENTS

what medium has been used in the grinding of pigments,
be it linseed oil, japan, varnish, or water, all are known
as " colors" either simple or compounded. The word
"pigment" is therefore much more restricted than
that of " color."

Strange as it may appear, this word has not yet
received its final definition. It is vaguely applied
to designate any substance that may be used in the
preparation of paint, fillers used in wood finishing,
etc. It is given to any solid substance used in com-
pounds, and is replacing that word in paint parlance
at least.

Strictly speaking, the name of pigment should never
be given to any substance unless it has the inherent
power of its own to impart color to other substances with
which it may be mixed. Originally it was used in this
strict sense only, and it should be so restricted. As it is
now, the adjunct substances possessing no coloring matter
of their own which are usually added to true pigments
with no other purpose in view than that of adding weight
without changing the original color of the pigments in
combination, are all called pigments too. It is a mis-
nomer. Possessing no coloring matter, the makeweights
are certainly not entitled to the name.

Correctives — sometimes useful adjuncts to a pigment
— are frequently of the same colorless character as the
makeweights, and therefore not entitled to be classed
with them. To illustrate exactly what is meant, the
following example is given: Starch and glue are solid
substances, but after they have been converted into thin
paste by the addition of hot water they are colorless, and
when they have been mixed with whiting or zinc or any
"colors," a distemper color has been prepared of which
either may form a component part, though not as a pig-

PRELIMINARIES 3

ment ; the addition does not change the color of the com-
pound in the least.

Here is another example: Liquid fillers, and fillers for
the light hard woods, contain some transparent solid sub-
stance, such as very finely ground silex, quartz, etc.; the
manufacturer in his pamphlets calls it the pigment part of
the filler. He uses it in this connection actually in place
of the word "solid." This is wrong, and befogs the real
meaning of the word, which originally seemed admirably
adapted to express the thought of coloring matter.

By courtesy some few substances will be designated as
pigments that do not possess any coloring matter of their
own to impart to other materials with which they are
mixed. For instance, barytes has no coloring matter to
impart to other pigments ground with it in oil or japan,
but when used alone in water it has a white color. Several
such substances which do not deserve to be classed as colors
when mixed in oil, have coloring when mixed with water;
and to save a double definition of them, the term " pig-
ment," which is applicable to them when in water but
which would not apply when mixed in oil, is nevertheless
retained in this instance, but to which they are really
no more entitled than is starch or glue. For similar
reasons, carbonate of lime (whiting), sulphate of lime
(gypsum) , finely powdered silicate stone or earths (silver
white or English kalsomine), will also be included in the
list of pigments, for they are properly so called when in
water (if not in oil).

To facilitate the search of any particular pigment, so
that they can be readily found without even taking the
trouble to look them up in the index, these have been
placed in groups of the principal colors, and all pigments
of that tone or order will be found under the proper
heading in the class to which they belong. The principal

4 MODERN PIGMENTS

pigment, or that which is mostly used, will be placed at the
head of the list, and others will follow in the order of
their usefulness.

Under each will be given, as far as practicable, a brief
historical sketch of its origin and derivation, its manu-
facture and preparation for market, its properties and
uses, the best and easiest methods of detection if subject
to adulteration, the enumeration of other substances
which are injurious and with which it should never be
combined, and, lastly, any other points of especial interest.

It was stated in the preface that it was not within the
scope of this book to treat the subject matter "pigments "
from the standpoint of the chemist or color-maker, and
reasons were given why; but the chemistry of most all the
pigment will at least be briefly noticed — simply the
giving of their component parts, or, where they have a
recognized formula, the giving of that. In a few of the
better known ones, a full enumeration of their constituent
elements will be given, as this is frequently an index as to
their character; but when the desirability for this occurs,
it will be done in a way that can be understood by those
not familiar with chemistry, and in words as free of
technical expressions as possible. A person needs not to
be a chemist nor familiar with that science to understand
a great deal of what constitutes the chemistry of paint;
good common sense will go a long way with the reader
to enable him to recognize the true from the false.

The researches and experiments made in the field of
color by eminent scientists within the last century —
many by men of the greatest ability, and who were guided
more by a love of attaining knowledge than with the
monetary inducements — have made the task of writing
up " pigments " a comparatively easy one. The author
cannot claim a great amount of originality, nor has he

PRELIMINARIES 5

made any great discovery himself, so that what he has
to say is none of his finding out, nor is it the first time
that it has appeared in print. The present treatise is, in
the main, one of compilation and arrangement. Nearly
half a century of practical handling of pigments, and
experimenting with them in paint factories and in the
ordinary practice of the paint shop, have helped him
form some decided opinions about the application and
mixing of most pigments, and upon this fund of knowl-
edge the writer has drawn freely and without stint,
and it is embodied in this treatise with that of others.

A good knowledge of the properties of pigments is
imperatively demanded of any one who wishes to be up
in the paint business, either as a dealer or user. There
is much to be learned about the proper mixing of pig-
ments and about vehicles suitable for the various pur-
poses: the future has a fine field for research in that
direction, for we do not know it all by long odds, and there
remains much to be revealed at some time or another.
Much of what is known now is not of such a character
that one can absolutely rely upon it; hence so many
opinions which are diametrically opposed to each other
about the preparation or application of the simplest of
mixtures. Humiliating as it may be to one who has
made a lifetime study of the paint business, the truth
requires and compels one to acknowledge as much as
appears above, for what now passes as orthodox in many
good paint shops, will be classed as rank heresy in others
of equally good repute. Therefore it is only by a thorough
and intimate knowledge of pigments, vehicles, and con-
ditions that any one can hope to grope to half-way
certainty in sundry instances, and to a fuller one in a very
few others. If it is so hard to get at the truth for those
who are constantly studying, what must the practice be

6 MODERN PIGMENTS

of those who do not study? Assuredly they can have
nothing but routine and guesswork.

There is much to be learned, — all are agreed upon that.
Chemists in the employ of paint manufacturers, and
others who are inclined to researches in the same direction,
usually make these their life hobbies; but as it is com-
monly on the side from their regular work, they are
somewhat hampered ; but every once in a while one hits
upon some process or other which is beneficial and help-
ful in the manner of fixing the coloring matter contained
in certain pigments more permanently than was ever
done before, or indeed it may be the discovery of entirely
new ones. Much has been done, but much still remains
to be done by the chemists. On the practical side,
however, there is still a great deal to be learned ; and here
is work for the thinking painters, and also for the asso-
ciations of master painters, who can do a great deal of
good by bringing together those who, while they differ
in opinions, can compare results, and thus aid in getting
at true solutions of vexatious questions.

Many important discoveries of the chemists were
prompted by suggestions made to them by the tests of
practical men. Theoretical chemists and practical men
generally cannot afford to work aloof from each other.
Either one without the help of the other is more or less
of a failure. Theory must be proved by practical tests
to be right. Many chemists are too apt to belittle the
value of suggestions made by well-posted painters, and
to regard them too much in the light of useful machines
for the proper application of paint. There can be little
wonder that many of their compounds and discoveries
of new preparations prove of no practical value. The
Patent Office at Washington, D.C., is a cemetery where
thousands of inventions in the paint line lie buried,

PRELIMINARIES 7

unknown and undisturbed, simply because of their
impracticability.

On the other hand, the painter too often looks at the
researches of scientific men with a sneer and turns up his
nose at them. All would find it advantageous to study
the writings, and make use of the information they would
find in them, of such men as Chevreuil, G. Field, L. E.
Andes, J. Lefort, A. H. Church, and many others. Unfor-
tunately, some of these men's works are now out of
print, and are to be found only in a few of the larger
public libraries.

The German language is richer with valuable scientific
works on pigments than is the English, but these are
very expensive, and mainly of interest to men well up in
chemistry. It is hoped that translations of some of their
best works may be made, adapted to the popular
understanding.

CHAPTER II
WHITE PIGMENTS

As it was stated in the preceding chapter, to facilitate
the search for any one given pigment, all have been
classed into groups of certain colors, and within each
will be found all which belong to it by being nearer in
tone than to any other group. It is fitting to commence
with the whites, as this group is the most important of
all. The whites are not only important to the painter
on account of its " self " color and the one self color
mostly used in painting, and rightly so on account of
cleanly tone and brightening effect, but also because the
whites form the base upon which nearly all tints are
made by the addition of colored pigments.

The ideal white pigment, is probably present to the aver-
age painter's mind, but the realization of it, as yet, has
been far from the ideal one. Every practical user of paint
who has given much thought to it, has some such ideal
pigment mapped out in his head. He has ideas of what
it should be like, — all good qualities, with none bad, —
but when he goes out among the realities of life and looks,
he does not find it. His ideal white pigment is to be found
only in his mind. A feeble portion of the good qualities
desired in a white are to be found unassociated with some
very bad ones in any one white pigment. In actual
practice it turns out that for every good quality shown,
there will be found a counterbalancing defect which
will prove a thorn in the flesh.

8

WHITE PIGMENTS 9

The above is written for the purpose of preparing the
reader for the defects which are found in all the most
prominent white pigments, and also to guard him against
over-confidence or extravagant expectations from the
use of any.

WHITE LEAD
History

White lead is the most prominent and best known
of any of the white pigments on the list. There are few
persons to be found, even outside of those connected with
the paint trade, but who are not more or less familiar with
or at least have heard of it in some way. Mankind has
known white lead a long time. It is of very ancient
antecedents. That the oldest civilizations knew it, is
evidenced by the remains of their pottery — the. glazing
upon it being obtainable only by the use of white lead.
Such Latin writers as Pliny and Vitruvius give the
process of its manufacture from lead and vinegar. It
was then known under various names, some of which
have come down to our own times, and which are used
to designate it to-day. For instance, "Cerusa, minium
album " in Continental Europe is still known as ceruse
and white minium. Recent excavations have brought
to light a number of well-preserved specimens of white
lead which show that it must have been an article of
common use in ancient Greece and Egypt.

The above details are given because many people
suppose white lead to be a comparatively new dis-
covery, or at best dating back but a few centuries. It
is true, however, that only a little over two hundred
years have elapsed since white lead commenced to be
manufactured on a large scale by what is known as the

10 MODERN PIGMENTS

"Dutch Process." Really, the principles of that system
are the same as those described by Pliny, the only dif-
ference being that a different application of the same is
made use of in the Dutch process.

While Holland has the honor of having given its name
to the process that is usually employed in the manufacture
of white lead to-day, that is, no doubt, due to the fact
that it was in that country that were made the first efforts
to manufacture it on a large scale in Europe. It had no
monopoly of it, for it was not long before manufactories of
it were to be found scattered in many European countries.
Factories were started in Germany, France, and England
not very far behind. Some of these brands of white lead
soon attained a high degree of excellence, and have
come down to our own times, their names being still
used to designate some very fine qualities, — such as
Cremnitz white, for instance, which was manufactured in
the city of Crems in Germany. Not within the past
hundred years has there been any white lead manu-
factured there, but the name still exists, the lead usually
sold under that name being a flake white. So much, then,
for good quality; for tradition still preserves it, and per-
sists in handing a name down to us more than a century
after the original had ceased to be made.

The Dutch Process

The "Dutch process" of corrosion has been handed
down to us with but few changes from what it was in
its primitive days. These changes consist only in more
sensible labor-saving devices for handling the various
materials used in the manufacture of white lead.

Before going into the description of the manufacture of
white lead by the "Dutch process," it will be best under-

WHITE PIGMENTS 11

stood if its composition be well studied; therefore the
chemistry of white lead will now be given.

The component parts of white lead vary somewhat in
the several specimens of it. { It is sometimes erroneously
called a carbonate of lead, but that it is not; at least, it is
not a pure one. If it was, it would be of little value as a
pigment, or rather its value would be greatly lessened.
Really, it is a combination of lead carbonate and lead
hydrate; the latter is what gives the saponifying and
binding properties. This hydrate of lead should be
present in the proportion of 30 to 35 per cent, and the
carbonate should enter the combination in the propor-
tion of 65 to 70 per cent. Lead hydrate has the property
of counteracting the chalking tendency of the carbonate,
but it has the drawback of rendering white lead less
opaque or more transparent. White lead should there-
fore in round numbers have two thirds of its weight of
carbonate of lead and one third of it the hydrate. Its
formula is 2PbCO3.

The usual process employed in the manufacture of
white lead is what is known as the stack system of the so-
called Dutch process, which name in reality simply stands
for the chemical process producing the corrosion of the
lead metal by the agency of dilute acetic acid fumes,
carbonic acid, hydrogen, oxygen, and heat. The exact
manner of conversion of the metal into a carbonate is very
imperfectly understood even at this late day by chemists,
who in their conclusions merely guess at it with more or
less plausibility in their theories. It would seem that
first of all it is converted into an acetate of lead, but as it
has more affinity for carbonic acid than it has for the
acetic, that it is transformed into that. As to the "how "
and "when," this is now clouded in mystery, and it still
remains for some one to satisfactorily explain.

12 MODERN PIGMENTS

Manufacture

The metallic lead used in the manufacture of white
lead should be soft and free from antimony, silver, or
any other impurity. If any of them are present in an
appreciable quantity the corroded lead will not be so
white and will also be specky. There are large refining
plants in the United States. The largest in the world
is located in Newark, N.J., where metallic lead is
desilvered at low cost, the silver obtained usually paying
the cost of . processing it. This desilvered metal makes
the whitest lead. Spanish lead used to be employed by
some of the eastern corroders, but what with the duties,
its scarcity and increased cost, it is now but little used.
Some is employed in making the finer qualities of flake
white; it makes a dense, and therefore more opaque,
white lead.

The pig lead — the large and heavy bars of metallic
lead as they come from the smelters — is melted into what
in corroder's parlance are called buckles. These buckles
are thin, perforated, circular plates of lead, and are about
one-sixteenth of an inch thick. The disk-like buckles are
placed in porous clay jars. These jars have projecting
knobs on the inside upon which the buckles rest. These
projections serve the purpose of separating the buckles
from each other in the jar. This allows a circulation of
air, heat and of the gaseous attacks of acetic acid vapor
reaching every part of the buckles, as it can ascend from
one to the other through the perforations. There is also
a large space left empty at the bottom of the jar into which
is poured dilute acetic acid of the strength of vinegar. As
vinegar owes what value it has as a corroding agent
to the acetic acid it contains, one can readily see that the
claim made by some corroders that they use actual

WHITE PIGMENTS 13

vinegar instead of dilute acetic acid, and making for this
a point of superiority, is all " bosh." It is very doubtful
if any corroder actually uses the vinegar of commerce,
notwithstanding the claims made.

After the jars have been filled with buckles to nearly
the tops, they are put into the " stack." To be more
accurate, the jars are placed upon the floor of the stack
in rows, and are filled from a large box containing buckles
of lead which come from the melting room and shaping
machine, and placed there in these boxes, which are
carried to the corroding stack houses on an overhead
railway which takes them wherever wanted, and from
which they can be raised and lowered at will. After all
the jars in the tier have been filled, the dilute acetic acid
is fed to each jar from a hose in short order.

The stacks themselves are compartments inside the
corroding houses. They are boarded up, and extend
from the ground floor to the upper one, which is the work-
ing floor. The diagram will give an idea of the arrange-
ment. The corroding buildings may be of any length
with any number or size of stacks inside of them. Many
of the big corroding plants have a number of corroding
houses. Some of the stacks inside of the same building
may be idle or in many of the different stages of corrosion,
each stack being independent of the one next to it. Thus
one can see in the same corroding house, one or more
stacks being filled up with buckles and jars, others
engaged in the corrosion process, while others again are
being emptied and cleaned out. It was stated that the
corroding agent was dilute acetic acid of the strength of
vinegar, but that without heat would produce an acetate
of lead only. So heat must be generated and carbonic
acid must be developed. To produce both of these, the
corroder uses spent tan bark, stable manure, or a com-

14 MODERN PIGMENTS

bination of both. Most people have seen how the market
gardeners generate heat in their hot-beds in the coldest
weather by using stable manure; the process is the same
that the corroder employs. A layer of this material is
first placed upon the ground floor of the stack, and
leveled up, and a layer of jars placed upon it. Upon the
jars a layer of boards is placed to keep out the next
layer of manure which is placed upon the boards, then
another of jars, then of boards, then of manure again,
and this is repeated over and o.ver until the stack has been
filled nearly to the level of the working alley above.

Each one of the layers in the stack has a chimney of
its own. This chimney consists of four boards nailed
together, and reaches to the top of the stack and acts as
an indicator to what is going on at each tier. The chim-
neys are kept open or shut according to requirements.

The heat generated by the tan bark and manure
vaporizes the acetic acid in the jars, and then the process
of corrosion goes on until all the acid has been evaporated
and all the heat has been spent. It usually takes from
75 to 90 days to accomplish this, and when it has ex-
hausted itself the layers are ready to take down. During
the generation of heat, carbonic acid is produced, and it
is from this source that it is supplied to the lead.

The pots when taken down are emptied into large
revolving cylinders which separate the white lead from
any that remains uncorroded. The white lead is after-
wards washed through several waters to free it from any
acetate of lead or from free acetic acid that may be pres-
ent with it. Acetate of lead is entirely soluble in water,
and can thus be readily gotten rid of.

The lead is then ground in water to free it still further
from any acetate remaining, and finally filtered through
a fine silk cloth which catches any specks of tan or

WHITE PIGMENTS 15

manure that may have found their way into the pots and
that the numerous washings of the lead have not removed.

The white lead is now run into large vats, where it is
allowed to settle. The "pulp/' as the mass of settled
lead is called, is taken to the drying pans, which are in a
separate chamber built for that purpose. This chamber
is fitted with steam pipes all around it, so that a very hot
atmosphere can be maintained until the lead in the pans
— as the large, low vats are called into which the pulp is
placed — is bone dry. •'

The lead is then crushed, and it is ready to sell, either
as dry lead for grinding with oil as white lead, or for
pottery use and the making of queensware and some
varieties of chinaware. Lead ground in oil is the only
form in which the painters usually see it.

To grind white lead in oil, the dry lead is first mixed
with the quantity of linseed oil necessary to grind it,
say about nine pounds and a half of oil to the hundred-
weight of dry lead. It is first triturated in revolving
mixers, from which it is carried mechanically to the
grinding mills proper, where it is ground either double or
single. The double mills pass the lead from the first to
the second without manual labor.

The speed at which the mills are made to revolve
during the grinding, and the lesser or greater amount of
heat developed consequently by that speed, make the
ground lead paste either tough and stringy in texture, or
else short and soft. The white lead itself has nothing
to do with it, as many erroneously suppose. From the
same batch of dry lead, the grinder can turn out either
kind or any intermediary degree between the two extremes
simply by adjusting the speed of his mills.

White lead after grinding undergoes some mechanical
change in its atoms, but the change is not a chemical

16 MODERN PIGMENTS

one. It should be perfectly cooled before it is packaged.
Many manufacturers put it in large, tank-like kettles,
which are surrounded with water. This makes the lead
more unctuous, and gives it better working qualities.
Lead so cooled will not harden in the packages, which
sometimes happens when it is run directly from the
grinding mills into them.

It was stated in the previous paragraph that lead
acquires smoothness and better working qualities when
it has been properly ripened in large masses before pack-
ing. Few manufacturers give it time enough for the
process to become completed; all are in a hurry to turn
over the product into money, and four to six months'
extra waiting is hard on them after all the time which
has been required since the pig lead was melted.

There is another system of grinding white lead, which
is known as the "Pulp Process." The manufacturers call
it, pulp ground, but in reality the lead is not ground at
all — that is, it receives no other grinding than that which
it received when it was ground with water previous to its
becoming pulp. In that condition it is certainly finer
than it is possible — or rather practicable — to grind the
crushed bone-dry lead in linseed oil by many repeated
grindings in the mills.

The wet "pulped " lead is run through presses by some;
but nearly all manufacturers who make a "pulp ground"
lead, withdraw the pulp as soon as it has settled down
from the water, and take it direct to a " chaser."

A chaser is a circular, low-sided vat, in which revolves
a heavy roller. This roller crushes and mixes liquids and
solids together into an homogeneous mass. Chasers are
used in preparing putty, etc.

White lead has a great affinity for linseed oil ; for water
it has none at all. The pulped lead having been placed

WHITE PIGMENTS 17

in the chaser, linseed oil is poured on it and the machinery
is set to work; the lead, having more affinity for the oil,
absorbs it, and the water is squeezed out by the weighty
roller, a way of escape being provided for it, and in a
short time it becomes displaced by the linseed oil which
has been absorbed in its stead.

There is no question about the fineness of pulp lead
if it has been properly ground before pulping it, nor can
there be any about its whiteness. Many have consider-
able doubts about the possibility of extracting all the
water out of the lead. Some well-posted men claim that
three to five per cent of it remain; others again put these
figures still higher.

Practical painters who have used pulp-ground lead
for years say that it has acted no better nor no worse than
other leads ground in the usual way. All, however, are
not a unit in this testimony, and some claim that it
chalks more readily. A person will be on the safe side if
slow in adopting its use exclusively, but should proceed
slowly in coming to a conclusion. By using it side by
side with the old kinds, and noting its action, in time
he may decide for or against its adoption. All things
being equal, pulped lead has some good points in its
favor,~ but time only, and lots of it, will decide its universal
adoption.

There seem to be very little and surely no material
differences in the methods of corroding lead used by the
lead manufacturers, excepting possibly that some few
have more mechanical labor-saving devices than the rest.
Few improvements have been made other than those
mentioned, and those mainly since the introduction of
steam and other motive powers which have replaced
animal and human energy wherever it was found practi-
cable.

18 MODERN PIGMENTS

To sum up the Dutch process of corroding white lead
in as few words as possible, it amounts to this: It is the
corrosion of metallic lead by aid of acetic acid, carbonic
acid, oxygen, and hydrogen.

When it was said in preceding paragraphs that there
have been no improvements to speak of in the manu-
facture of lead by the Dutch process, this was meant in so
far as the original application of the principle and of the
system carried " on by the Dutch and other European
corroders of the long ago, — the stack method.

There is a new way of applying the same principles and
agents of corrosion used in the Dutch process. Manu-
facturers who corrode lead in the new way, claim that
they produce a white lead which has absolutely the same
chemical composition as that produced by the stack
system, that its atomic formation is the same, that its
working qualities are the same and in some respects
better, — in short, that it is the same.

It is not intended to pass an opinion upon the claims
made by these gentlemen, nor to certify to their verity.
What is here said must not be construed into an unquali-
fied indorsement of them. They have some strong
cards in their hands, and they seem to understand how
to play them. That their system of corrosion saves
much time and many manipulations, cannot be gainsaid;
that it appeals to the intellect as being more progressive
than the other, is also true. It gives the manufacturers a
more perfect control of the action of the corroding
agents in the process of corrosion, thus placing them in
a position to make more uniform products.

Several manufacturers representing millions of capital
have been corroding by the cylinder system for the past
twenty -five years; others are adopting it in America and
European countries. In the United States some two or

WHITE PIGMENTS 19

three factories using that system have a very large out-
put. The practical men, the painters who use it, are
seemingly well satisfied, so it looks very much as if the
system had passed out of the experimental stage and that
it was going to remain with us.

This cylinder method is very simple and easily under-
stood. To all intents and purposes other than the
manner of making the white lead it is entitled to have
its product called " Dutch process " white lead as well
as that produced by the stack system — if the
proposition laid down in a former paragraph be the
correct one. It is repeated below in a shorter form:
That the name " Dutch process" stands for lead
corroded by the agency of acetic and carbonic acids,
oxygen and hydrogen.

The operations for the corroding of lead by the cylinder
system are few. In the first place, the pig lead is melted
and poured in a stream against which a jet of steam is
made to play. This pulverizes the lead into fine, sandlike
particles. This lead sand is placed in revolving cylinders
connected with generators wherein acetic acid and car-
bonic acid gases or vapors are evolved, and hydrogen and
oxygen supplied to the cylinders at will, the supply
being regulated so that correct proportions of each will
be available during the period of corrosion.

The particles of lead sand, being so very small, are
quickly acted upon by the corroding agents, as the slowly
revolving cylinders keep this fine sand in constant com-
motion so that no part of it can remain unexposed to the
direct action of the attacking vapors, the particles con-
stantly changing their location and presenting new
faces to their attacks. Thus in a few days is accom-
plished what would have required months by the older
system.

20 MODERN PIGMENTS

The cylinder system excels the stack system in more
ways than one. The corrosion is more perfectly done, and
there remains but a very small percentage of " blue "
lead — as the uncorroded lead is called — compared
with the other system. To all intents and purposes, it
might be called a complete corrosion.

As most of the condemnation of the white lead produced
by the cylinder system can usually be traced to those
financially interested in the white lead produced by the
older system, one should take such statements with the
allowance of a grain of salt, and discount them to their
just values.

It is presumable that poor lead can be and is produced
by both the stack or cylinder systems; and again, that
good lead can be made by both. If a lead is perfectly
white, fine, free of surplus moisture other than that which
chemically belongs to it; if it has good opacity and
excellent working qualities, — we need have no hesitation
in using it whether it has been made by one or the other
method.

Properties of White Lead

White lead stands head and shoulders above any other
white pigment — in so far as opacity or covering proper-
ties are concerned — when ground in oil or japan. Con-
sequently it is used more than any of the others; in fact,
much more than all the others put together several times
over. Its working qualities under the brush are superior
to any others, this being caused by the white lead com-
bining chemically with the linseed oil and forming a
linoleate lead soap which works freely and smoothly
under the brush, enabling the painter to apply it evenly
with a minimum amount of labor.

WHITE PIGMENTS 21

It is not alone useful as a white pigment for painting
surfaces in its own or self color, but it is used to even a
larger extent as a base upon which all the lighter tints
are made by addition of coloring matter.

Were it not for a few defects, white lead would certainly
be the ideal white pigment instead of being only the most
useful one. It has already been hinted that a lead which
contains too much hydrate of lead in its composition
would be somewhat deficient in opacity, and that if it
contained very much more than two thirds of the car-
bonate it would be likely to chalk badly, or worse
than the ordinary. No matter what the proportions of
hydrate and carbonate the white lead may have in its
composition, in time it will chalk if exposed to the action
of the elements.

In the best leads the process of disintegration (for
that is what chalking means) commences in about one
or two years after its application, usually in an inappre-
ciative manner, and continues until in time one can rub it
off the building by simply passing the hand over it. As
stated, this chalking is very gradual and hardly notice-
able at first. The chalking can be hastened or retarded
somewhat by the improper or proper use made of the
binding vehicle; also by the improper or proper admixture
of other pigments.

White lead is a good drier of linseed oil, and requires
but a very small admixture of artificial driers to hasten
its drying; and out of doors, excepting in cold or wet
weather, none are needed. Driers seem to kill the elasti-
city of linseed oil, and to hasten its decay, so that when
used at all in connection with white lead, it should be
done with very modest doses.

Only raw linseed oil should be used with white lead for
outside painting. The raw oil is much more elastic and

22 MODERN PIGMENTS

penetrating than the boiled, nor will the chalking com-
mence as soon when it has been employed than it would
otherwise.

The greater the quantity of raw linseed oil that can
be incorporated with the lead and make it cover fairly,
the longer the time before chalking will begin. It stands
to reason, therefore, that as a small proportion of volatile
oils should be used in outdoor painting in addition to
raw linseed oil as will accomplish the legitimate end in
using it at all, i.e., of rendering the paint more fluid and
of making it set more quickly. The above applies with
even greater force to the last or finishing coat, where
volatile oils should be dispensed with entirely wherever
possible to do so. It is somewhat harder work to
properly spread paint so mixed, — that is admitted, —
but it can be done. White lead seldom chalks upon
inside work that is not exposed to the weather, and what
has just been said is not applicable to indoor painting.

White lead is injuriously acted upon by the action of
sulphureted hydrogen vapors, which will quickly turn
it black. That gas converts it into the black sulphide of
lead. This will sometimes occur m a single night, there-
fore its use should never be resorted to in localities where
this gas is likely to develop.

There is one grade of white lead which is best known as
flake white. It differs in no wise from ordinary lead
excepting in that it is a selected white lead. The flakes
which drop off the buckles corroded by the stack system,
have given it the name. This outer covering of the
buckles is superior in opacity to that from which the
flakes fell off and which comes next to the core or uncor-
roded lead that is more imperfectly corroded, and which
in ordinary lead is averaged with the flakes and forms the
white lead of commerce. Therefore flake white desig-

WHITE PIGMENTS 23

nates a quality of white lead of superior corrosion and
which possesses extra good body.

The same objectionable features enumerated as apper-
taining to ordinary white lead, apply to this with as
much force. It is used mainly by decorators and sign
painters for striping in car shops and carriage factories,
for coaches, buses and wagons, — in fact, wherever an
extra good-bodied lead is demanded.

Every nation has its own system of packaging, grading
qualities and marketing white lead, therefore one will not
find the same rules nor trade customs in the United States
as prevail in the United Kingdom, nor upon the continent
of Europe.

In the United States an unwritten law has developed
which says that upon all packages on the label of which
the manufacturer's name is placed and the words
" Strictly Pure" are used — that the contents of the
package are free of any adulterating material and
contain nothing but pure white lead ground in pure
linseed oil.

It is, however, true that some jobbers mark some fake
leads as strictly pure, which are far from being so and which
are adulterated to the bitter end; but then, they withhold
from them their own names and adopt some flaring name
or label which misleads no one aside from the unsophisti-
cated and ruralists who wish to buy pure lead at half its
market value.

So if a lead package put up in the -United States bears
no corroder's name nor the legend " Strictly Pure" upon
it, one may take an oath and swear that its contents are
adulterated. He can do so without ever having seen an
analysis of it, and without the least fear of committing
perjury. None such is pure. It is an adulterated lead,
or what is known as a compound lead.

24 MODERN PIGMENTS

It is not within the province of this treatise to enter
into an endless review of the merits or demerits of com-
pounded leads, nor of the superiority and better wearing
qualities claimed for them by their manufacturers over
that of the strictly pure.

There can be little doubt, that proper combinations of
other pigments with white lead are beneficial for many
purposes. The painter should be well enough posted to
do this compounding himself to suit the particular job
upon which the compound is to be used. Certain com-
pounds or combinations of pigments are better adapted
to sundry conditions than they are to any other; and no
ready-prepared compound, even when honestly made
after a uniform formula, is likely to meet his requirements
fully in this regard, however good it may be for the right
place.

A man well posted upon the various qualities and
defects of the white pigments should be able to pick out
the proper corrective ones to combine with white lead to
suit any job. If it be old, open or spongy, it certainly will
require to be treated differently from a surface which is
close or non-absorbing.

There are, no doubt, very good lead compounds upon
the market which will give desirable results for painting
under certain conditions to which they are admirably
adapted, but which will cause some trouble and always
mortification elsewhere. As a rule, there is no real
advantage to be gained from their use. They are not
as economical as those similar in composition and com-
pounded at the shop from strictly pure white lead and
other correctives bought as such.

Barytes, or the native barium sulphate (heavy spar),
plays an important function as an adulterant of white
lead ; for that matter, it does in the adulteration of nearly

WHITE PIGMENTS 25

all other pigments. But it is preeminently adapted as
a makeweight for white lead: its heavy weight comes
nearest of any other to that of white lead. Its trans-
parency, too, in oil is another reason why that substance
is so well adapted for the purpose of its or any pigment's
adulteration, because it will not discolor them. More
will be said regarding barytes under its proper heading,
and the reader is referred there for the particular details
and characteristics belonging to that pigment. The one
object why it was entered into here is because it was
necessary to point out the main source of adulteration in
connection with the "off brands" of white lead as are
best known and called all brands of lead that are not
strictly pure. Compound leads which are sold as such,
are not included in the "off brands," but are known in
the trade as "compounds."

Compound leads are not necessarily adulterated leads,
because in the first place they do not claim to be strictly
pure lead. They are legitimate articles of commerce,
and stand upon their own merits. Painters buy them
with a full knowledge of what they are, and from having
had some previous experience with them, which in some
instances has been well paid for.

The same substances which may be used in a legitimate
way in a compound lead, and of whose presence the buyer
is well aware, may be and are rightly called adulterants
when combined with lead which the purchaser is led to
suppose is pure white lead.

For this reason, gypsum, china clay, carbonate
of lime, or even the sulphate of lead, which are all
used in the adulteration of white lead, are not such
when the purchaser buys a compound lead, as the
attempt is not made to parade them as something which
they are not.

26 MODERN PIGMENTS

LEAD SULPHATE

This lead salt is never sold under that name in the
supply stores. It is only within a comparatively short
time that it has come to be talked about in connection
with paint or mixtures of paint.

It is a by-product of several industries, and until lately
it has had but little commercial value other than that
which inherently belongs to it, as, if it could be
reduced to its metallic form, it would be worth the price
of metallic lead less the cost of conversion, which is
expensive.

It can be readily made by simply adding sulphuric
acid to the solution of a lead salt; then it becomes^ pre-
cipitated as a white powder which is insoluble in water
and absolutely so in alcohol.

Its insolubility makes it non-poisonous. If it pos-
sessed a good body, or, in other Words, had it more opa-
city, it would be a very, desirable pigment^ It is not as
pure toned a white when ground in oil as is white lead.
It is not readily affected by the vapors of sulphureted
hydrogen. Its chemical formula is PbSO4.

Sulphate of lead is never used alone as a pigment, but
as an adjunct to some brands of white lead, and largely
so in ready-mixed paints. Its chief use in paint mate-
rial manufacture is for such grinders as put out a brand
of white lead which they mark as strictly pure. It
enables them to place a product upon the market for
which they can vouch as strictly pure lead, but is no
more entitled to be so called than sugar of lead would
be. When sold as "strictly pure" lead, sulphate of lead
is as much entitled to be called an adulterant as barytes,
other substances which have no business to be

WHITE PIGMENTS 27

It is used advantageously in color making — such as the
lemon or canary chrome yellow — but in the above they
are really the result of the use of sulphuric acid in
the making of the color, and not because they are placed
there.

SUBLIMED LEAD

Sublimed lead is a certain form of sulphate of lead
which is obtained by sublimation in Southwestern Mis-
souri, and to which much of what was said of sulphate
of lead proper does not apply. While it is still somewhat
deficient in opacity as compared with hydro-carbonate
white lead, it comes next to it in that respect, and is
used extensively by mixed-paint manufacturers in pre-
paring those goods.

It is basic sulphate of lead; contains about one fifth
of lead oxide and about five per cent of zinc oxide — the
ores from which it is made containing zinc in combination
with the lead. It is sublimed in a manner somewhat
similar to that described under tne heading of Zinc White.

One property entitling it to consideration is its non-
poisonous character. Another good point is that being
an oxysulphate of lead it is not subject to turning black
by sulphureted hydrogen gases, and is so extremely fine
that it does not settle readily in an oily vehicle. It is
also very white when mixed in oil, which cannot be said
of sulphate of lead.

DAHL PROCESS WHITE LEAD

This form of lead pigment is obtained by precipitation.
By a modified method of manufacture, it is much superior
to the product obtained originally. In this modified
process it is first reduced to a downy or feathery state,
after which it is placed in stationary tanks where it is sub-

28 MODERN PIGMENTS

jected to the action of dilute acetic acid which converts
it into a basic acetate of lead. The solution is subjected
to the action of a stream of carbonic acid, which, as already
said, lead having more affinity for it than it has for acetic
acid, combines with it, and is precipitated in the form of
basic carbonate of lead.

It differs from Dutch and similar process leads in that
instead of being crystalline it is amorphous in its par-
ticles. It therefore does not possess quite so much
opacity, but is a greater absorbent of linseed oil. Natu-
rally from its amorphousness it is very fine, and runs
uniform in composition. It is, however, too soon to form
a decided opinion of its merits, whatever it may present
theoretically.

WHITE OXIDE OF LEAD.

Periodically somebody or other discovers — or rather
thinks he does — something new in a white pigment of
lead derivation which in his estimation is sure to
displace the hydrate oxide of lead, and that his discovery
is sure to fill the "long felt want" of a pigment — one
that is white, non-poisonous, not injured by noxious
gases, and for which they claim a string of virtues too good
to be true and too numerous to mention. These great
discoverers appear as regularly as the seventeen-year
locust, and the wreckage of the last of them is hardly
cleared away before somebody else turns up ready to
launch out a new venture which proves similar to the
ones which have gone before; but as it is launched
out under a new name, it takes a little time before it is
recognized.

It seems that some people will never learn that oxides
of lead all have the property of solidifying into a hard

WHITE PIGMENTS 29

mass inside of the package containing them in the shape
of a ground paste, if ground with linseed oil. Yet one
after another of the discoverers seems to be able to enlist
men with capital to back their foolish ventures, and men
of good business capacity and caution in other respects
try to accomplish the impossible — i.e., grinding lead
oxides with linseed oil.

The white oxide, the monoxide (litharge), the bioxide
(red lead), the teroxide (orange mineral), all have the
same peculiarity of solidifying in time when ground in
linseed oil. When the retailers who are not posted, have
keg after keg returned to them after a few months —
with occasionally a claim for damages — it proves to be
the beginning of the end for " oxide of lead " in that
locality.

Some in sheer desperation have gone so far as to grind
it in soft linseed oil soap, as, when ground in that, it
remains in a smooth, soft paste; but, as one could readily
expect, it is soon found out and the " jig is up." The
history of defunct concerns in this connection would make
good reading on short-sightedness for the rising generation.

There have been, and some firms are to-day trying,
experiments with other salts and forms of lead. Time
may prove some of value; none so far have any claim
to superiority over the old hydrate-carbonate. All as
yet have so many defects that the very grave ones
admitted as belonging to white lead look small compared
with them.

The Blowpipe Test

Adulteration in white lead and many other forms of
lead is readily detected by the use of the blowpipe.
This simple test is within reach of every paint dealer or
painter. It is simple and easily made: A piece of soft
charcoal, such as is made from willow, to lay the lead upon,

30 MODERN PIGMENTS

an ordinary candle or spirit lamp, and a blowpipe. This
is simply a small metal tube curved at the end. The*
curved end has a very small aperture, and that is placed
against the flame of the candle while the operator blows
in the other end of it; this throws a stream of blue flame
from the candle to the charcoal, or to that part of it
rather where the lead is laid upon it, the operator holding
the piece of charcoal in his left hand. The blowing
should be regular and steady, and in a minute or two
at most the oil will be burned out, and the white lead
will be converted into a blue lead globule.

If it has been adulterated with lead sulphate, barytes
or whiting, china clay, etc., the lead cannot be reduced
to a metallic state by any amount of blowing. There
will be a mass of dry white, yellowish or grayish color
according to the adulterant, but no lead will show up.
As small a percentage as 10 per cent of adulteration
mixed with the lead will prevent its reducing; as no
lead is ever adulterated with such a small percentage
as . that, there will be no difficulty in finding it with the
blowpipe.

If the adulterant is sulphate of lead, it can be found by
the great difficulty of its reduction; few men can use the
blowpipe steady or long enough so to reduce it, as it
takes much more heat to do so. That form of it men-
tioned as sublimed lead is practically irreducible by the
blowpipe; it takes over 1200° F. So one may look with
suspicion upon any white lead that does not readily
reduce in two minutes.

One can form a good idea of the purity of lead by putting
a little of the lead paste upon a sliver of pine wood, and
burning a match or two underneath it. If it is pure, little
globules of metallic lead will appear in the paste, which
will not be the case if the lead is impure.

WHITE PIGMENTS 31

The blowpipe test is valuable only to test the purity
of hyd-oxi-carbonate of lead — the white lead of com-
merce. It will not apply to many of the white salts of
that metal, as some fuse only at extreme temperatures
or by the use of fluxes which none but experienced men
can conduct successfully.

The present tendency in some quarters to recognize as
" white lead/' in a commercial way, the basic sulphate
of lead or sublimed lead would of course nullify the test;
but why, if, as claimed, oxy-sulphate of lead is superior
to Dutch process hyd-oxi-carbonate — the standard white
lead of commerce — should it seek to shelter itself under
the name adopted for an entirely different pigment?

Will it not be better for both to retain their present
designations which have a definite meaning, and if sub-
limed lead proves itself the superior, it should be entitled
to a distinctive name by which purchasers can purchase
it with a certainty that it has not been adulterated with
Dutch process lead, and it should not seek to shelter itself
under its time-honored appellation?

The above is written not as a disparagement or as an
indorsement of one or the other forms of leads, but in
hope of saving the white lead and sublimed lead indus-
tries from future confusion, whereas now the two are
distinctly known and recognizable under their commercial
cognomen.

CHAPTER III
WHITE PIGMENTS (Continued')
ZINC WHITE
History

V— /

ZINC WHITE as a pigment is of much more recent origin
than that of white lead, and does not date back much
farther than threescore and ten years. It was known
before that, and it had been used in water colors a few
years previously. As an oil pigment, however, it may be
called a recent one. It would in all likelihood have been
used for years before it was, but for the difficulty en-
countered in making it dry properly; and writers in the
beginning of the nineteenth century incidentally mention
the probability and possibility of its becoming a useful
pigment. However, it was in the forties that it was first
used as an oil paint with a drying oil by Leclaire in France.
From that time to the present, its use has steadily grown
and extended.

It took a long while at first to break down the pre-
judices then existing against its use, and which even now
prevent many from using it. So the advent of this pig-
ment to popularity has been slow. It has had a hard
time to establish itself firmly.

Chemistry and Manufacture

There are two very distinct qualities of zinc white.
The better quality is known to the trade as " French"

WHITE PIGMENTS 33

zinc, and the other as " American" zinc; both have the
same chemical composition, — oxide of zinc.

French zinc is that which is made from the zinc metal,
while American zinc so-called is made directly from the
zinc ore. It will be seen that the terms used to designate
these two qualities are more arbitrary than strictly
true — at least, such is the fact to-day. It does not do
America justice to call the poorer zinc after it, but, as we
have seen in the case of Cremnitz white, names stick. No
amount of reasoning is likely to change it any more than
in another glaring instance, i.e., English and American
Venetian red.

The French are • no doubt entitled to the honor of
having first used this valuable pigment; also of having
first produced it in a commercial way; so that importers,
brokers, and paint manufacturers gave it the name, and
habit still forces the name to remain. France never had
a monopoly of its manufacture, and Belgium produces
one of the most esteemed of its brands — the " Vielle
Montagne" zincs.

Within the past twenty or twenty-five years, works
have been established in the United States which are
producing zinc oxide by the "French" process which is
certainly equal in quality to that made in any country.
It is sold as ''French " zinc, and the grinders pay as good
a price for it as for that which is imported.

The process of manufacturing zinc white is very sim-
ple. The metal is vaporized by heat in retorts, whence
it is carried to a chamber where the vaporized zinc comes
in contact with air containing oxygen, for which
element it has a great affinity. It combines with the
oxygen, and is at once converted into an oxide of zinc.
This oxide of zinc is gathered into a series of sacks or
small chambers suspended with the mouths opening

34 MODERN PIGMENTS

downward. That which is lightest and whitest is
deposited farthest from the point of entrance of the
vapor; the heavier is also the darker and is deposited
nearest. This darkness is caused by impurities con-
sisting mainly of unconverted metal, which prevent the
grading of the zinc white as first quality.

Zinc oxide made thus is very light and flocky,
resembling in a manner snow or eiderdown. It is
selected and graded according to quality, whiteness,
etc.; after which it is submitted to the action of
powerful compressing machinery under intense heat;
then it becomes the article of commerce known as
"Dry Zinc White."

Vast quantities of it are annually consumed in that
shape for distemper work, for the better class of kalso-
mining, etc.; either alone as a white, or in combination
with whiting or gypsum or with coloring matter in the
making of certain tints.

For use in linseed oil painting, it is ground either in a
strong drying oil which has been previously treated to
discolor it, or in drying poppy seed oil for the finer grades
of work.

It is usually packed in tin cans ranging from one to
twenty-five pounds each. Both the French and the
American zincs are sold in two qualities according to
their whiteness. The whitest and best is sold as Green
Seal zinc white, while that which is of a darker shade is
sold as Red Seal. These are usually found in the output
of all grinders of zinc, and they have come to be under-
stood as meaning first and second quality. They are
used upon all grades of zinc ground in linseed oil or poppy
seed oil, except upon the very lowest and cheapest grades
of American zincs, which, in addition to being of poor
zinc, are usually adulterated.

WHITE PIGMENTS 35

American zinc is made in precisely the same manner as
that described for French zinc, with the exception that
instead of using zinc metal, zinc ore is employed in its
place. It is made from the vaporization of the ore, the
oxidation being the same; the process in all respects being
identical, and so are the after treatments.

From the impurities contained in the ore, one may well
surmise that the product cannot be equal in either white-
ness or quality to that made from the metal itself. Both
systems are now used in the United States, but, as stated
before, it is only in recent years that it has been made
here from the metal.

The chemical formula of zinc white is ZnO. It is the
only oxide of that metal and the only one of its many
salts that is of any use as pigment to the painter.

Tests for Purity

The purity is easily tested. If it is in a dry powder,
it will dissolve readily without effervescence in either
dilute nitric or hydrochloric acid.

If it has been adulterated with barium sulphate, that
substance will not be acted upon by the acids. It will
be left undissolved in the shape of a white powder at the
bottom of the dish. If there is effervescence during the
dissolving of the zinc white by the acids, the presence of
lime in the shape of carbonate of lime or whiting is plainly
indicated.

If the zinc to be tested is ground in oil or varnish, it
should be agitated thoroughly in benzine or naphtha,
which will dissolve the linseed oil out of it. Let it rest
and deposit after the agitation has been thoroughly done,
then pour out the benzine and repeat the same operation
until it is thoroughly free from the oil. After drying the
powder — which will be done quickly if left in the open

36 MODERN PIGMENTS

air — it can be used in the test precisely as was described
for the dry zinc white.

Zinc white is not affected by sulphureted hydrogen
gases, nor by sulphurous vapors of any kind.

Properties and Uses

Oxide of zinc, or zinc white as it is best known to the
paint trade, has had its praises sung to all kinds of tunes
in every civilized country where paint is used. It
deserves a good deal of this admiration, and is one of the
most valuable additions to the list of white pigments, and
really is indispensable in the well-regulated paint shop.
It should be used as a component part in many a mixture.
But much of the praise we hear should be carefully
weighed and conclusions slowly reached. It will hardly
do to swallow the whole of the flattery, at least not to the
extent some would have it, that of discarding the old
standby, white lead, and substituting for its use that
of zinc white. While some of its friends are extravagant
and unquestionably go too far, it is nevertheless an
excellent pigment in its proper place. When judiciously
used, it is invaluable, and will give every satisfaction. If
used, as it sometimes is, in a haphazard, hit-or-miss sort
of way, it will not take many years before sorrow will
come of it, and the painter's reputation goes a-fishing.

For interior work in either distemper or enamel, zinc
white is greatly to be preferred to any other white pig-
ment, and its praises may be sung in a very high pitch.
Then it deserves the homage of every painter and
decorator in the land. Its freedom from the attacks
of white lead's greatest enemies — sulphurous fumes —
compels its use under all circumstances where these are
present.

WHITE PIGMENTS 37

It is true that the French government is throwing its
influence in favor of the use of zinc and discouraging the
use of white lead, and has passed some very stringent
legislation in regard thereto. Simmered down to its real
value , this means that journeymen painters in that
country, either through bad habits or careless use of
white lead, are more subject to lead poisoning than those
of other nations. These have circulated petitions, held
mass meetings, and have forced upon the attention of the
government what they choose to call " the evils of white
lead." The legislation in a great measure is the result of
this agitation. True, nothing but zinc can go on to public
buildings, etc. This is heralded and made use of to the
limit, by those most interested in its manufacture and
sale; nevertheless, when all the facts in the case are fear-
lessly looked into, it means but little.

All public buildings, and nearly all others of any sort,
are of stone in France. The painting is principally that
of the interiors and some of the doors and blinds, which
are usually painted in colors and not with zinc on the
outside. Some few are painted white, or in tints made
from white zinc as a base, and they show very plainly that
had the government been as careful to take the advice
of more practical men instead of that of theorists, and
had not to knuckle under the goods handled by the
journeymen who are voters, and their friends who are
voters too, there would be less cracked paint to be
burned off than there is to-day and will continue to be.
It is only a question of time when the practice will have
to be abandoned, as the French are no greater lovers of
eyesores in the shape of paint scales than any other
people.

The particles or atoms of zinc white have a great
affinity for each other. As has been already related

38 MODERN PIGMENTS

when describing the manufacture of zinc white, the
atoms cling together like snow or eiderdown interweaving
each other, and that they are compressed by powerful
machinery. This adherence and brotherly embracing of
each other in these atoms is remarkable, and stands as the
very opposite of that of the atoms of white lead, which
have no affinity whatever for each other. This in part
explains why lead chalks so easily. When the binding
of the linseed oil which holds the atoms together
begins to decay, they begin also to drop and loosen
from each other — they fall singly, having nothing to
hold them.

The reverse condition takes place with zinc white. Its
atoms have such an affinity for each other that they hold
together in a solid mass. When the oil has so decayed
that it can no longer bind the zinc and hold it against the
building, the paint cracks and gradually loosens from
it, forming a scale which will eventually drop away in a
mass in the same way and manner as the bark does from
the Buttonwood or sycamore tree.

While the use of zinc white alone for outside painting
is not to be recommended, a combination of it in proper
proportions with white lead will in a good measure
counteract the inherent defects appertaining to each.
The tenacity of the zinc white will retard the falling away
of the white lead; and that, in return for the good deed
done it, will help to prevent the excessive tenacity of the
former.

There can be no set rule formulated giving the exact
proportion that each should have in making up a com-
bination. Under certain conditions, lead paint to which
25 per cent of zinc white has been added may crack and
scale, while again under others as much as 60 or even 80
per cent would not affect it injuriously.

WHITE PIGMENTS 39

As this treatise is written for the purpose of giving
information that concerns pigments, and not upon the
application of paint, details therefore which properly
belong to a book on painting cannot fully be elucidated
here. Possibilities are indicated to show what the
properties of the pigments are and how to correct some
of their bad points. Generally speaking, therefore, a
paint for ordinary surfaces should not contain more than
20 to 25 per cent of zinc to 75 or 80 per cent of white lead
for outside painting. The figures given are conservative,
and circumstances might alter them considerably.

The non-drying properties of zinc white have already
been mentioned. It is therefore necessary to add some
driers to the linseed oil used in its application. This is
especially the more essential if raw linseed oil be used ; and
it is really the only one which should be employed in con-
nection with zinc white for outside painting, on account of
its greater elasticity, which lessens its tendency to crack
and scale, by lengthening the period until decay com-
mences.

For distemper painting, aside from its beautiful white
tone when used alone, or the clearness of the tints made
from it and the addition of coloring pigments, it has also
a soft, satin-like finish impossible to produce with whiting
or gypsum whites. Therein lies the secret of many a
kalsominer, whose work is so much superior to that of
others who do not use it and have not discovered its value.
The former are looked for and kept busy while the latter
are looking around for work. The clearness of tints made
with zinc is not confined to distemper work, but is still
more strikingly noticeable when tints are made from pig-
ments ground in oil, and zinc white in oil or poppy-seed oil.

CHAPTER IV

WHITE PIGMENTS (Continued)

THE EARTH WHITES

General Remarks

EARTH WHITES are so named to distinguish that class
of white pigments which owe their origin to mother earth
in contradistinction to those which are derived from a
metallic origin, as lead and zinc.

None of the earth whites are as valuable to the work-
man in oil, painting; in this respect they are entirely
different from the metallic whites. When mixed with
linseed oil, they assume a dirty, dingy, measly-looking
white. All are more or less transparent, or at best are
semi-transparent. By themselves they may be called
useless as oil paints, but, for all that, some are very useful
when employed as adjuncts to the metallic whites in oil.
Their usefulness lies chiefly in the correction of some
defects, and that is their chief use in connection with that
vehicle.

In kalsomining and distemper work they become true
pigments in every sense of that word. They impart a
color of their own to the other pigments with which they
are mixed. In water, they are invaluable.

Lime, clay, and silica, with admixtures of other sub-
stances in small quantities, form the basis of nearly all
the earth whites. According to which of them mainly
enters into the respective compositions and predomi-
nates, they are known by various names.

40

WHITE PIGMENTS 41

Most all the earth whites are to be found in abundance
in many parts of the world. Most of them are cheaply
mined and prepared for use, consequently they are inex-
pensive. This cheapness makes them very attractive
for compounding with white lead or zinc white, openly so
in the goods known as compound leads, etc., or secretly
so in the preparation of the "off " brands. The greatest
harm that any of them do in either the off brands or the
compound leads is that they reduce the covering proper-
ties in these in nearly the same ratio as the quantities
into which they enter. It is said " nearly," but as some of
these earth whites are semi-transparent and have cover-
ing properties of their own, it is true therefore in the
main of most of them. Their spreading possibilities are
increased, and pound for pound they spread farther than
lead, so that a greater number of square yards can be
painted with a given weight. This is due to the fact
that they absorb more linseed oil than does white lead.
This makes them wear longer, and helps to protect the
lead in the combination. Some of these earth whites
have strong caustic properties; this causticity saponifies
the linseed oil, and as the saponification formed is a
partially soluble one, it is necessary to be careful of their
use.

CARBONATE OF LIME, OR WHITING
Chemistry and Source of Supply

Carbonate of lime, or whiting as it is popularly called,
whose chemical formula is CaCO3, is plentifully supplied by
nature in a nearly pure state in the shape of chalk. It is at
least pure enough for use as a pigment after the removal of
the coarser substances mixed with it, such as silica and
other impurities, by levigation. It is sometimes made

42 MODERN PIGMENTS

artificially from certain varieties of limestone, which in
the United States is more abundant than chalk.

The principal source of supply is chalk. That is the
natural carbonate of lime. All it needs is crushing and
afterward levigating.

Levigating is the technical name used to designate the
operation of washing out the impurities present in all
natural earth pigments. Whenever that word is used
in this treatise in subsequent chapters, one will under-
stand that it is employed to designate the washing out of
impurities consisting of heavy sand, pebbles, roots, etc.

After the chalk has been crushed or powdered, this is
mixed with water and thoroughly agitated, that it may
all be dissolved and held in suspension by the water. It
is then run off, conducted through pipes to a succession
of vats where the liquid mass overflows from one to the
next, and so on. The finer atoms being the lightest
they are held in suspension the longest, and they flow
to the farthest vats before depositing, the sand and other
heavy impurities settling in the first ones, so that the
quality of the settlings increases or decreases according to
the longer or shorter distance of the settling vats from the
first of these where the outflow starts.

The first, second, and third vats contain nearly all the
worthless substances, which are usually thrown away.
The rest are graded according to fineness. The pulp
is then dried, crushed in large lumps or powdered, packed
in barrels, and the last is sold as " Gilder's" whiting-
chalk which has simply been crushed and powdered
without having been subjected to the levigating process
is known by the name of "Commercial" whiting.

The qualities and styles of packages which a few years
ago were to be found upon the market under various
fancy names have nearly all disappeared. For in-

WHITE PIGMENTS 43

stance, the small cones of Spanish white, the brands
of Paris white, London white, etc., are seldom to be found.

Some decorators prefer what is known now as "lump"
whiting. This is not lump chalk, as some might suppose
it to be. That would be too hard to dissolve, — in fact, it
would not dissolve; besides, the impurities lump chalk con-
tains would bar it from use by that class of workmen.
Good lump whiting is the same as the best grade of
gilder's whiting, with the only difference that after the
levigated pulp is dry, instead of being powdered it is
simply broken up into chunks for the handy packing
of it in barrels.

That it is better than the corresponding quality that
has been powdered, is claimed by some decorators. It is
a question requiring a Philadelphia lawyer to decide. It
is too hard for the ordinary mortal to answer. It is a rem-
nant of the times when the old bosses used the dabs of
Spanish white, which were just pulp dipped out and dried
in cone-like shapes, and were in those days known to
every painter in the land. But to-day, with powerful
machinery to crush the whiting, and if this has been well
levigated, it looks as if the powdered whiting had the
best end of the arrangement. It dissolves in water more
readily than the lump, therefore is more desirable for
the painter's use, because it saves his time.

Properties and Uses

Whiting is a very good distemper pigment, and is
probably more extensively used than any of the white
earth pigments. It is used chiefly by kalsominers, deco-
rators in distemper painting, and in immense quantities
by the wall-paper manufacturers in preparing their print-
ing tints.

44 MODERN PIGMENTS

In linseed oil it is very indifferent, to say the least.
From its causticity, it must be very active in saponifying
and destroying the linseed oil. It never dries very hard
with it, and where the oil has been applied thick, it will
skin over the soft stuff underneath and will come off with
but little provocation. It always imparts a dull, dirty
tone to any tints made by adding coloring matter to it,
or to white lead compounds where it predominates. For
employment alone, its transparency is against it. Small
quantities of it added to the megilp used by grainers
will make the color comb better and permit it to be put
on heavier, and still be more transparent than would be
possible without it.

There are several cretaceous earths which at times have
been used as paint or adjuncts to white lead, but none of
them have proved very satisfactory. Their use is now
obsolete. Far better substances can be had which are
fully as cheap as whiting. The chief use of whiting is
in water-color painting, and in this connection it is con-
sumed in enormous quantities. The wall-paper printing
industry uses it in the preparation of its tints. The
kalsominers and fresco painters also are large consumers.
The putty manufacturers also employ it in the prepara-
tion of that article.

rv
CHINA CLAY, OR KAOLIN

China clay is the only white earth pigment that has
any body in oil, but even the best samples could hardly
be called semi-transparent. This class of white earth is
also known under the general names of argillaceous and
clay white. It varies greatly.

Properties and Uses

The kaolin, or china clay of commerce, is the best repre-
sentative of the class. It is nearly a pure clay, and that

WHITE PIGMENTS 45

is why it is better bodied than the cretaceous or silicious
earths. It is very much better than whiting as a com-
ponent part of off leads and lead compounds. Never-
theless it is far from being an ideal substance; it has
some grave defects of its own, but it has a better body,
and is not an active destroyer of linseed oil.

Its defects are that it dulls the tone of white lead, and
that it muddies that of tints in about the same manner
and for similar reasons as whiting does.

It is also useful as a distemper color, working nicely
under the brush; but as it does not make as smooth a
job as whiting, it is therefore very seldom employed for
that class of work.

Its chief use is that of an extender, as an adulterant
in off leads or compounds, ochers ground in oil, Venetian
reds, etc. Its greater body, heavier weight, and being
much less caustic than carbonate of lime, render it much
better adapted for purposes where these qualities count.

But in common with all earth pigments which contain
a large proportion of clay or alumina in their composi-
tion, the great trouble is that clay has the property of
absorbing water and of parting with it readily. This
hygroscopic property is lessened when mixed with oil,
but not altogether eliminated. After the oil has
thoroughly dried, and from exposure and decay become
porous, clay pigments absorb water from the atmosphere,
and when the heat of summer comes, this moisture is
given out. This is the main reason why so much trouble
has been reported from the use of ochers. There is no
doubt that in the majority of cases, this was due to the
use of an ocher which contained a very large percentage
of alumina in its base.

This constant absorbing or parting with moisture is
bound to produce blistering, and later on scaling, and is

46 MODERN PIGMENTS

the principal cause of mildew. It also causes the sinking
in of colors, which means a cloudy, fady, muddy, uneven-
looking surface.

GYPSUM (SULPHATE OF LIME)
History and Provenance

Gypsum is plentifully found in the natural state — a
soft rock — in nearly all parts of the globe. It is known
to every one in its calcined condition under the form
and name of plaster of paris. In this form, however, it
is of little use as a pigment. It is therefore chiefly in
its uncalcined condition that it will be considered.

It is first levigated and freed from impurities in much
the same manner as has been related was used to clean
chalk from its impurities. It is chiefly in this condition,
after thorough drying, that it is useful either as an adjunct
to other pigments, or as the principal ingredient in all the
so-called anticalcimine, gypsine, etc., — the prepared dis-
temper paints whose manufacturing headquarters are
located in Grand Rapids, which is situated in the heart
of the gypsum beds of Michigan.

Properties and Uses

For distemper purposes and water colors, gypsum is
well fitted, although it does not work as smoothly as
whiting, nor does it make as solid a covering. In some
other respects it is superior to it; it has much better
tenacity and adhering properties. It is better to buy
it ready prepared for application. It requires a long
experience in its preparation. This the manufacturers
possess; and experimenting continually, they have been
able to correct some of its faults and to put out a line of

WHITE PIGMENTS 47

goods which is much better than any thing the painter
could possibly prepare for himself.

In relief work gypsum is the principal substance used
in the mixtures.

It is also useful in oil, not so much as a pigment as an
adjunct; as a corrector or betterer, if it maybe so called.

It has some of the defects of other earth whites, the
main one being its transparency. It possesses no opa-
city in oil, or next door to none. When used excessively
it dulls tints the same as the rest of them. Unlike many,
it has no causticity, so that it does not injuriously affect
linseed or any other of the fixed oils. Therefore when
used judiciously with white lead, it will retard its chalk-
ing, for it is a good absorbent of oil, and is inert. But
it must be used in reason, or it will make the white lead
look off-color and too transparent.

It is also used by color makers as a base for certain
colors, but of that more will be said as occasion will
require under the proper heading. It is chiefly in that
connection that its usefulness lies.

Chemistry

Sulphate of lime when calcined at a heat of 110°C.
loses its water of hydration and forms the well-known
article of commerce, plaster of paris.

In that condition it absorbs water readily and recom-
bines with it, returning to its hydrate or natural condi-
tion. This renders it unfit for use as a pigment, as it
would harden when mixed with the water used to thin it
in distemper work, and would absorb enough moisture
from linseed oil, which contains a small percentage, and
from the atmosphere, which at times is heavily charged
with it, to harden even when ground in oil. When it
has become heated to 500° C. then it loses the power of

48 MODERN PIGMENTS

absorbing moisture, and it is in that condition that it has
to be for the purposes of the manufacturer of pigments.

It is never found in that shape in a commercial way,
and for that reason the painter cannot avail himself of
its use in order to compound it with other pigments.

Should the future demand for gypsum of 500° C. be
found to grow, it is highly probable that manufacturers
will grind it in oil. At the present it is known only to
few aside from the color makers, so there is no market
demand for it. Probably the reason is that it is a very
hard substance to grind after such high calcination.
When it enters in combination with other pigments it is
much easier ground, and it is always in that shape that
it is ground.

SILICATE EARTHS (SILVER WHITE)
Properties and Uses

Silver white is known to most painters, probably not
as a paint or pigment, but as an ingredient entering into
the preparation of fillers.

It is hardly worthy to be called a pigment, as, even when
mixed with water for distemper work, it shows but little
opacity, and is very inferior to either the cretaceous or the
argillaceous earths for that purpose. The chief use is in
correcting some of the evil tendencies and defects of
white lead and zinc white. As correctives, then, the
silicate earths are excellent, and are better adapted to
that purpose than are the earth whites of either of the
two classes described before. Their benefit is great, and
the time is not far distant when a paint will hardly be
considered perfect that contains no silicate earth in its
composition.

WHITE PIGMENTS 49

The above statement may be considered by many
as claiming too much, and it may possibly be so; for it is
really possible to make very good paint without it, but
such was not in mind when it was uttered. The cost of
making a good paint without its use being greater, the
chances are that there would be but few so made, and so
the truth contained in the statement remains anyway.

Composition and Chemistry

Silicate earths, as may well be surmised and as the name
indicates, are mainly of silica or sand; but this is so fine
and the atoms so minute, that in the best grades of it,
they are held in suspension in liquids a very long time before
precipitation takes place — the particles will almost float.

The silicate earths occur in various parts of the United
States in natural beds, and for once Dame Nature has
endowed America with an earth useful in painting which
is superior in fineness and quality to anything that has
been found so far in any of the European or Asiatic
countries. The products of American mines are exported
extensively. That will never be the case with its other
natural earth pigments, such as the ochers, umbers, and
siennas.

The beds containing silicate earths are mined like all
the other earth beds, according as to whether they lie
near the surface or are located quite a way below it.
The raw earth is levigated to clean it from heavy sand and
other impurities, for while it is nearly of the same chemi-
cal composition as sand, — which is another form of
silica, — that is as much of an impurity in a silicate
earth as that same sand would be if found in an ocher.

In some of the beds of silicate earths the product
obtained is said to be so nearly pure and free from foreign
matter as to hardly require levigation to fit it for use.

50 MODERN PIGMENTS

It is again repeated that silicate earths are really not
pigments in the sense that these can or do impart color,
and their usefulness as correctives and for compounding
with other pigments is their chief claim.

Silicate earths have no affinity for water or moisture,
and are absolutely inert when mixed with linseed oil, nor
will they injure it in any way. The atoms are so very
fine, that they mix intimately with those of either white
lead or zinc white to the great benefit of both of those
pigments. They will dry hard without any tendency
toward chalking, cracking, or peeling off, and, but for its
lack of opacity, would be as near the goal of being an
ideal pigment as can be well conceived. Its use should
become more popular than it is now for all kinds of out-
side painting.

Its value can be inferred by what can be noticed almost
anywhere, or by making the experiment for one's self
any day. Take some white lead, or white lead and zinc,
either in the pure white or with color added to make any
tint, and paint the side of a building with it afterwards,
and while the paint is still fresh, sand half of it, then
notice what the consequences will be — say in five years.
The unsanded lead will be in a bad state of chalking; the
lead and zinc will be in a better condition, but still will
begin to show signs of decay; while that part which has
been sanded will be on as tight as the day it was put there.
The silica did it. This is invariably the case; and as it is
a common practice for many places exposed to being
marred or defaced to be sanded, one will have little trouble
to find samples of it already so painted which have been
put on for many years. It can thus be seen and the results
ascertained without having to wait several years for it.

The good wearing qualities of the French and English
ochers are due to their being silicate ochers; they contain

WHITE PIGMENTS 51

a large percentage of silica in their base. (See the chapter
on ocher.) Had the silicate earth but the opacity of
white lead, it would be worth its weight in gold, as the
saying is, as a pigment for general painting; but it has
not that quality.

Many of the most valuable colored pigments are
natural earths containing a large percentage of silica in
their composition, which will be properly noticed under
the several headings to which they respectively belong.

BARYTA WHITE (BARIUM SULPHATE)
Composition and Provenance

Baryta white is better and more commonly known as
barytes in the United States. It is found commercially
of many different grades and qualities. It is obtained in
its natural state in many parts of the world. It is well
known under the form of " heavy spar," which is a heavy
crystalline rock. It is found in localities of many-vary-
ing geological formations. Near Quincy, Illinois, it is in
large quantities in the limestone formation of the bluffs
along the Mississippi River, also in the Blue Ridge region
of Virginia and elsewhere. Again, it is found in the zinc
and lead mines of Southwestern Missouri, Northwestern
Arkansas, Southwestern Kansas and the Indian Territory.
It is somewhat ludicrous, this finding of it in connection
with lead in mines — as if that substance knew that later
on it should be made to parade as and become a still
closer neighbor of lead under its new form of "white
lead/' and made to renew an acquaintance with its old
neighbor where they had lain together for ages before
being disturbed from their peaceful slumber by the
miners.

52 MODERN PIGMENTS

Properties and Uses

Barytes is very transparent. It is the ideal trans-
parent pigment element, heavy spar being nearly as
transparent as glass. When ground in linseed oil, ordi-
nary barytes has no body. This can be best seen by the
mixing of barytes with oil, and of painting a board three
coats with it, the same mixed to the usual consistency
of paint for a like purpose. It will be found that these
three coatings, which had they been mixed from any of
the usual pigments would have covered the board per-
fectly, in this instance have not even hidden the tracery
of the grain of the wood. It will be safe to say that one
single coat of white lead would have covered the surface
of the board more opaquely than five coats of the barytes
paint would do.

That barytes must be a very heavy substance may be
surmised from the great weight of the heavy spar from
which it is prepared. It is by reason of this heavy weight
that it is the chief adulterant used to doctor up white
lead. It being nearly of the same specific gravity, it is
thus admirably adapted to pass inspection where the
lighter weight of better adulterants would be a "dead
give away" on account of the greatly increased size of
a package of a given weight. That is why whiting,
gypsum, etc., are so seldom used for the purpose of adul-
terating white lead. They would make entirely too much
bulk, and the fraud would be recognizable to a novice.
Therefore barytes has almost a monopoly as an adulter-
ant of white, its heavy weight entitling it to that eminent
position. Another requisite which is of as nearly as
much importance, is that of its great transparency. More
barytes can be added to white lead without muddying
its color, than of any of the earth whites of better body,

WHITE PIGMENTS 53

but which change the color of the pigments they are
added to, as has been already said of them.

Barytes is also the adulterant chiefly used in the mak-
ing of the cheaper colors in oil; this, however, more on
account of its transparency than that of its weight; as for
many of the lighter-weight colors it is greatly against it,
— it makes the package look too small. Its transparency
usually decides the scales in its favor, as the chief make-
weight adulterant even for the light-weight colors, some
very light-weight adulterant being used in connection
with it to give more bulk. Its transparency does not
greatly affect the tone of the darker colors with which
it is used; and while it can be detected when the adul-
terated color is -used in making tints — it renders them
less clear in tones — it will hardly show in the color itself
in self-color painting.

In such extra light-weight colors as Prussian blue,
lampblack, etc., it cannot possibly be used alone, as it
would be an easy "give away; " so, as was said, it is usual
to marry it to a much lighter-weighted partner, but it
goes in just the same.

To show the capacity of barytes as an adulterant and
its transparency, fifty pounds of it can be added to one
pound of dry Prussian blue medium chrome yellow or
lampblack without changing the colors greatly. Thus
the enormous quantity of fifty to one is within the possi-
bilities in adulterating with it. While seldom used to
that extent, it is sometimes found in nearly that ratio in
the "cheap John" lines of colors in oil occasionally to be
seen — frequently more in the cheap dry colors.

While upon the subject of adulteration it might be well
to say here that in a general way colors are not adulter-
ated to anywhere near the limit of the possibilities as
that of fifty to one. More frequently the adulteration

54 MODERN PIGMENTS

will be found to be one to one, three to one, or four to one
of the genuine color; the latter being the common one
in use, and recognized as justifiable for the proprietary
greens and many other colors which do not indicate
purity by any such claim upon their labels. This adul-
teration is, however, to such an extent, but will be found
in many whose labels would, to the unsophisticated,
create the impression that the colors were pure — with-
out saying that in so many words.

As it is mainly as an adulterant that barytes has any
serious claims upon the attention of the readers of this
treatise, this is the side from which it is viewed.

Not so, however, of the artificially prepared baryta
white, which is better known to artists and decorators as
"blanc fixe." The latter is an excellent pigment for
water-color painting, and nothing of what has been said
of the natural barytes applies to that, except its lack of
opacity in oil; but even in that, it is head and shoulders
above the ordinary barytes. In water-color work, it
possesses a good body. It is a perfect white, absolutely
unalterable under all and any circumstances or conditions.
It is insoluble in the acids, and is not attacked by sulphu-
reted hydrogen gas nor any other sulphurous vapors.
It is of great value for uses wherever the painting is sub-
ject to such influences where most of the other whites
would be unsuited. Its absolute permanency recom-
mends it for the highest grade of decorative work,
and where the reputation of a man depends upon
the intact preservation of his work. It cannot be too
highly prized.

It has another very important qualification aside from
those of permanency and whiteness, in that it has a
peculiar texture that is entirely its own, and this remains
even in the tints made by its use. The same pleasing

WHITE PIGMENTS 55

peculiar finish cannot be reproduced with anything
else, no more than cotton can be made to have the
feel of wool.

The artists and decorators are the ones who are mainly
interested in its use. It is never likely to pass into the
hands of the general house painter.

The reader should remember to distinguish between
barytes and baryta white or blanc fixe. Dr. Dudley, chief
chemist of the Pennsylvania railroad, has had a great
deal to say of it, and is probably as good an authority
upon barytes in all forms as can be found the world over,
he having made that substance the subject of much
investigation and experiment. He says that some forms
of the atoms in certain grades of barytes are scale-like,
and overlap each other in such a way as to intercept the
rays of light, and that when colored up with proper pig-
ments the barytes does not show transparent. The
doctor must have come across a brand that is hard to
obtain outside of Altoona. The author has never yet
seen it, nor has he ever seen or heard of any one else who
has seen it in such a shape.

There is a legitimate use for barytes as an extender,
especially in such colors as the greens or chrome yellows,
which in their pure state are very strong. That state-
ment should be understood in this sense only: For
instance, one pound of pure chrome green or chrome
yellow is worth, say, 25 cents per pound. Another one
containing 80 per cent of barytes can probably be bought
for 12 cents. Now for solid painting the last will go about
as far as the pure, and cover the surface well. The latter
will be the cheaper for this use, so the extended green or
yellow is the most economical for solid painting. Where
colors, however, are bought for the making of tints, and
where the amount of coloring matter they contain is the

56 MODERN PIGMENTS

one thing most needed, the pure color will always be
found most economical.

The above concludes the list of useful white pigments.

Many others have come up from time to time, staid
a little while and were found wanting, or of less value than
these which have been noticed in the two preceding
chapters. They have about all disappeared, and the list
of them would read too much like an epitaph, and would
be a needless burden.

CHAPTER V
YELLOW PIGMENTS

OCHERS

General Characteristics

YELLOW ochers are natural earths found abundantly in
all parts of the known world. It is of small wonder then
that among the most ancient and earliest attempts at
chromatic embellishment that have been unearthed and
brought to light as a result of searches made in the
entombed remains of former civilizations, many objects
are found whereupon ocher had been used by some pre-
historic decorator.

This yellow was used in the making of many an ingen-
ious design upon the covering of the Egyptian sarcopha-
guses. In America the Aztecs especially, and the wild
tribes of Indians roaming the plains and mountains of
North and South America, used ocher also in such decora-
tions as they were able to design and execute.

The Aztecs being the better civilized of them all, one
would naturally expect more and better decorative work
from them than from the wild migratory tribes; and
they have not disappointed expectation, as remains
of their pottery and decorated household utensils will
show.

In Asia, ancient objects of Chinese and Tartaric origin
have tracings of it upon them. The Greeks and Romans
used it profusely; and so far there has not been a nation

57

58 MODERN PIGMENTS

found, where the earliest attempts at decorations have
been preserved, that ocher does not appear as one of the
pigments.

Of its uses to-day little need be said. It is a household
word, and its praises are sung by everybody interested
in using it, let him be painter, decorator, or artist. After
white lead, it is probably the one color that any of them
could least afford to discard.

Chemical Properties and General Character

All ochers are compounds or mixtures of several
ingredients or substances. The coloring matter they con-
tain is due to hydrate ferric oxide combined with an
earthy base which varies with each locality, and some-
times with every hill in the locality where they are found.
They will vary very much in the same vein of the same
bed. Different seams in the vein are often of diverse
composition, and are sometimes separated in the mining
operations.

There cannot be therefore any recognized standard
nor chemical formula for an article varying as much as
this does. They would have to be changed with each
new sample that was analyzed.

Notwithstanding so many variations, ochers may be
grouped into two general classes:

1. Those where the earth base holding the iron oxide
is chiefly of silicate earth.

2. The remaining ochers whose base consists princi-
pally of clay earths or alumina. There is a vast difference
between these two classes of ochers, not only in the work-
ing qualities of each, but in their tones and permanency.

Then there is between the two classes mentioned above
an intermediate one comprising such as vary in the
quantity they contain of either silica or alumina, making

YELLOW PIGMENTS 59

it sometimes difficult to class them properly, as they come
to the border line of each of the main groups.

Mining and Production

Volumes might be written upon this one pigment
alone without exhausting the subject matter. While
it might be attractive to a specialist in colors, much of
the matter would have but little interest to the general
reader.

Ocher is mined and obtained from the bowels of the
earth in many different ways, depending upon the depth
required to reach it, or to the topography of the
surface of the land. The price of labor and advancement
in civilization, and the consequent use of labor-saving
machinery, come in also as factors in the problem of
mining. Sometimes shafts are sunk to it in level
sections of country if the veins are deep. If, on the con-
trary, they lie near the surface, an open cut is made to
the veins, and they are simply elevated, or, better still, a
track is made and the ocher shoveled right into the car.

In the hill sections where it occurs as an outcrop above
the valleys, it is tunneled out and loaded in small cars
which are run out on a track in much the same manner
as coal under similar conditions. In many beds, seams
are found where for a few feet or inches a better grade
of ocher is found than in the rest of the vein. If it be
found to be very much better, it is shoveled out separately
and handled by itself.

In its natural state, ocher is usually mixed with many
impurities, such as roots of trees or plants, sand, gravel,
etc. For the cheaper grade, or what is known as " un-
washed " ocher, the earth after having been brought
from the mines is simply sifted through a screen and
barreled. Only the very lowest or ordinary ocher is sold

60 MODERN PIGMENTS

in that way, and the bulk of it is washed, and the very
fine qualities re washed ; but with the system of continuous
settling tanks it is seldom practiced any more, as the
very finest can be obtained from the farthest tanks.
This is equal practically to rewashing, and the method
was described under the heading of "Whiting." It is
needless to repeat it in this connection, as it is the same,
there being no difference in the operation nor its principles.

As already told, the finest is that which settles in the
tanks situated the farthest from the outpour, and the
settlings are graded accordingly as extra fine, superfine,
double washed, single washed, etc. These washings or
levigations are no index to the quality of an ocher, and
only signify the greater or lesser freedom from impurities
contained in the ocher.

There is still another method of mining ocher, which is
sometimes employed in hilly countries. A dam is built
across a valley with a sluiceway at its lowest level, through
which the water from the pound resulting from damming
the valley can be let out or kept in by shutting the gate in
the sluiceway.

After the heavy spring and early summer rains are over,
the mining commences. Hydraulic machinery is used,
and streams play upon the ocher beds in the hills adjacent
to the valley. This dissolves them and washes down the
earth into the pent-up valley below; after a sufficient
quantity has been washed out, which is gauged by the
capacity of the pond formed by the dam, it is allowed
to settle. When the water has cleared, it is allowed to
escape through the sluiceway, while the ocher remains
as a pulpy deposit. It is left in that state to dry out by
the action of the sun's rays. This requires some little
time, and in wet seasons there is considerable risk attached
to this method of mining; but there is usually nice weather

YELLOW PIGMENTS 61

in the autumn, when it is taken advantage of to handle the
ocher.

By this system the heavier impurities are deposited
long before reaching the pond, and little else than the
ochered water reaches there, as the gravel and roots are
screened out early in the runways through which the
flow is made to reach the pond. The sand settles all
along its course, or at its first entering into the pond; that
which has been held in solution until it reaches the main
part of the depositing pond being usually a fair quality of
ocher which requires no further washing for ordinary use.

When the pulp has dried sufficiently, teams are set to
work with plows and scrapers, and are loaded with the
loosened ocher earth and hauled out to the packing sheds,
which are roughly constructed affairs, but sufficiently tight
to keep the ocher from rain and consequent damage.
There it is again pulverized, screened, barreled, and placed
either in cars for shipment or in storage warehouses.

This method is by far the cheapest way of handling
ocher, but it is limited in that it cannot be made contin-
uous. It is ingenious, and might have been the invention
of a Down East Yankee, but that is not so. It is that of a
plodding Pennsylvania Dutchman; at least, he was the first
one to put the system into use in America, and possibly
in the whole world. His works are situated near Allen-
town, Pennsylvania, and are located in a small valley
through which is a runlet which gives the water a chance
to reach the larger streams, but which is usually dry
except during the heavy spring rains.

Properties and Uses

The statement was made that ochers could be grouped
into two general classes, and so they may for the purpose
of examining their characteristics and properties.

62 MODERN PIGMENTS

The two extremes are taken as types, but in reality
there are some ochers that are so near the half-way mark
between the two types, that it takes a good deal of guess-
ing to tell where they rightly belong. Besides, there are
any number of grades from the one type down toward the
dividing line forming the line of demarcation of the other.
Speaking in a general manner, the bulk of European ochers
belongs to the class of ochers containing a silicate base,
while those found so far in America are more argillaceous
or alminous in character, and may be so classed.

If the reader bears in mind what was said concerning
the silicate white earths under that heading, he will have
no trouble to understand why ochers with a silicate base
are much better than those having a clay base, at least for
the painting of surfaces exposed to the weather. He will
also understand why the clay ochers are best adapted to
distemper work.

One half of the lamentations which many painters
indulge in because of the troubles they have had, caused
by the use of ocher, and in the airing of which they at
times fill the columns of the trade papers, can be easily
traced to the use of the wrong ocher. Investigations
will always show that it was an ocher with a clay base
that was the disturbing element.

One never hears of troubles from those painters who
use the silicate-based ochers under the very same condi-
tions where the other kind is said to have gone wrong, and
these can hardly find words good enough to utter the
approval they have to give.

Both are truthful in the telling of their experiences, but
while each has to tell them from the use of a pigment
which has the same name and possibly the same color,
each is in reality speaking of something of an entirely
different nature and properties.

YELLOW PIGMENTS 63

The troubles had by those who used the clay ochers
are of the same nature as those to be expected from the
use of china clay, as has been related in the former chapter.
Clay ochers when thoroughly dry have parted with the
moisture which they originally contained. If a building
is primed with such an ocher, it may be called hermeti-
cally sealed, especially if the priming was a heavy one, as is
usually put on for cheap two-coat work. This heavy
priming has practically sealed up the wood and prevented
the penetrating of the second or finishing coat, the fine
particles of the clay and oil combining to make a poreless
glazed surface. The supervening coat put over it dries
in much the same way as it would upon a piece of glass;
it is not able to anchor itself into the non-porous priming.
If the priming had been composed of white lead alone, or
of white lead with a reasonable quantity of zinc with it,
and put on not too heavy, the priming would have been
porous. The finishing coat of lead, or lead and zinc, put
over a heavy clay ocher priming, dries upon the surface
without clinching itself to it, because it is non-porous.
This coat naturally dries thoroughly, having contact
with the atmosphere, and becomes porous after the linseed
oil has lost its glyceride. The ocher underneath is reached
through these pores by the moisture in wet weather,
which it will absorb in sufficient quantity to make
trouble. During dry, hot weather, this absorbed moisture
will be drawn out of it in the form of steam or vapor.
Much of it will escape through the same pores by which
it entered, but some may not because of a surplus of
moisture finding its way to some porous part of the wood,
and when the heat is great, the steam not being able to
escape as fast as it is formed, forms a blister under the
coat or coats applied over the clay ocher priming, and there
is trouble. This absorption and evaporation continually

64 MODERN PIGMENTS

going on tend in time to loosen the superadded coat or
coats and to make them part company from the priming,
which usually remains intact. This is one of the main
causes of complaint made against the use of ocher as a
primer.

Silicate ochers have no such effect. Silica does not
absorb water. It has no affinity for it, consequently
there can never be any of it, either by absorption or other-
wise, to escape out of it in the form of steam during
warm weather, so that there is no danger of the super-
added coats coming off it, as related of the clay ocher.
Being more porous, the finishing coat becomes anchored
to it, and if it has been properly compounded will remain
attached as long as it would upon a lead priming. It is,
of course, possible to mix a finishing coat of dope, but
such would come off of anything it was applied upon, and
this is not a matter for serious consideration.

All kinds of ochers are great absorbents of linseed oil,
and should be bought ground in oil rather than in the
dry state, unless one possesses good grinding machinery,
which is something very unusual.

As may be readily understood, the mere percentage of
strength of the colored matter (hydrate ferric oxide) con-
tained in an ocher is not always a criterion whereby to
judge of its quality or actual value. The better grades of
French ochers seldom contain as much as 25 per cent of
ferric oxide, and usually much less than that.

Every painter and decorator is pretty well acquainted
with the high character of some of the French ochers,
also with some of the English of the Oxford class. These
last are considered the best found in England, and justly so.

The following analysis is taken from Church's "Chemistry
of Paints," and was made by Professor Church himself
from a sample of ocher which was taken from the Shotover

YELLOW PIGMENTS 65

Hill mines near Oxford, and which he says represents
fairly the quality of the Oxford ochers:

Hygroscopic moisture 7.1

Combined water 9.0

Ferricoxide . ..... ......;. . 13.2

Alumina 6.3

Silica . . . -. . . 61.5

Calcium sulphate .' .. . . 1.4

Undetermined 1.5

100

The above analysis shows nearly two thirds of the com-
ponent parts of that ocher to consist of silica, therefore
one can pin his faith to it for all kinds of outdoor painting.
But note the comparatively small percentage of ferric
oxide, the coloring matter.

The French ochers proper are somewhat richer in the
proportion of oxide of iron contained in them than that
of the sample cited above. Notwithstanding that they
average stronger in coloring matter than the Oxford
ochers, they are commonly of a lighter and brighter tone.
This is remarkable, because ochers which usually contain
large proportions of ferric oxide, are darker than those
which contain less. It is very hard to account satis-
factorily why it is that some samples are so much richer
in tone than others of nearly the same chemical compo-
sition. Some lack in brilliancy, or, if not in that, are found
lame elsewhere. It is therefore useless to look to a
chemical analysis for a reason to explain these things.

Some of the better grades of French ochers make
beautiful cream and buff tints with white lead or zinc
white — so rich in fact as to suggest to one used only to
the American ochers that possibly they had been doc-
tored up with chrome yellow. This richness is inherent,

66 MODERN PIGMENTS

and the tints made from them will never fade, as would
those from a chromed ocher.

It is customary with many color grinders to tone up
ochers with chrome yellow. When this is done, and sold
under the proper name, and labeled as a "Chrome Ocher,"
it is all right. That is a legitimate transaction; but
when this is done to tone up a poor ocher so that it will
sell better, then it is all wrong, and is bound to work an
injury upon the unwary users of it.

If such ochers are used for solid painting, the chrome
yellow will fade away, leaving the ocher its original ugly
color. If such an ocher has been used in making tints,
the rich tone will disappear even more quickly.

The painter using these may possibly have saved a
quarter of a dollar in the difference of cost between a
good French ocher and what he used in the making up
of his tint if the house was a good-sized one, but in repu-
tation the loss cannot be computed in quarter dollars.
Had he used the right ocher, the gain would have been
permanent; the customer would have been better satis-
fied, even if he knew little about color. Every neighbor
seeing the house holding its color so well and so long
would have become a free "ad" for the painter. The
wishy-washy, fady, spotty-looking house is another
kind of an "ad" loudly proclaiming that the man who
did the job did not know his business.

Page after page of ocher analyses might be given, but
would only confuse the mind. All they do or would
prove is that there is no such thing as uniformity to be
found in them, and this has been said so often here that
it is unnecessary to prove it again by crowding in useless
testimony.

The reader has been advised to buy his ocher ground
in oil. There are good reasons for it.% Manufacturers

YELLOW PIGMENTS 67

of reputation are much more careful buyers than the
average painter can be. They know how and where to
buy pure French ochers. They have men in their employ
who are experts in this line. They can buy direct from
the importers, if it be so that they do not import it them-
selves, and will receive it in the original packages from
the custom house as imported. The painter who thinks
he can tell unerringly a French ocher when he sees it, or
who depends upon the stenciled marks on the barrels
bought from his supply houses or the jobbers, will in nine
cases out of ten be imposed upon. Besides, the best
reason of all is, that allowing he can buy just the same as
the manufacturer, he certainly cannot afford to grind it.
The grinding of a good ocher should never be done in
an iron mill, as, when it is so ground, it is likely to lose
brilliancy, or at least impair some richness. Stone mills
are the only ones fit for grinding ocher, or, for that matter,
all other colors, including the blacks, if brightness of the
color is of any object — and it surely ought to be. The
above is said for the benefit of the painter who is thinking
about the buying of a paint mill so he can buy his colors
dry and pure (?), and save his hard-earned dollars instead
of giving them away for colors ready ground. The man
who owns a collection of paint mills, and has them
rusting away down in the back part of the cellar, knows
better, and the advice given does not concern him. All
the money that a painter has ever saved by the grinding
of his own colors can be put inside of a very small pocket
book, and in old-fashioned copper cent cart-wheels at
that.

Grinding colors so that they retain their brilliancy of
tone, and are ground to the last degree of fineness, is a
science and trade by itself. The painter can never learn
it thoroughly, nor can he equip himself rightly for it except

68 MODERN PIGMENTS

at too great an expense for it ever to pay him to do so.
There is quite a capital tied up in such an equipment,
which in an ordinary shop will be required to work for
possibly one week out of the fifty-two in the year. This
machinery will have to lie idle fifty-one weeks yearly.
There will be nothing for it to do. If he intends to keep
it going so as to sell to others, all right and good — but
then the painter will find it more profitable to give up
the painting business, as he cannot expect to make a
success of both at the same time.

There are few shops, aside from those of large railway
systems, where the grinding of colors has ever been done
advantageously. In these there is a set of men whose
sole business it is to attend to the grinding, and who, if
they are not expert grinders at the beginning, soon become
skilled by keeping constantly at it. Even in these large
shops there is no economy claimed by the master mechan-
ics. The cost of installing and maintaining the grind-
ing plant, and the wages of the employees detailed to
that work, more than eat up the difference in cost between
the dry pigments and the ground goods prepared ready
for thinners, bought in large quantities, as these shops do.

The large capital invested in expensive machinery
which is constantly needing repairs soon disgusts the
most enthusiastic, and, like all dearly bought experience, it
comes to stay with them. Hence the discarded machinery
in the cellar, or that which goes to the scrap-iron heap.

This lengthy advice and warning is given here, not so
much because it appertains to ocher more than to any
of the other colors, but because ochers being the first ones
of the colored pigments under consideration, it seemed
best to give it under that head, and it will not have to be
repeated again. Such advice and warning is needed,
and if followed it will save dollars to the man heeding it.

YELLOW PIGMENTS 69

During a lifetime, the author has visited in one capacity
or another for nearly fifty years several thousand paint
shops. In a very few he has seen mills set up; in many
more he has seen the self-same mills relegated to some out-
of-the-way place. In all instances where the owners were
asked about the saving effected by their use, the reply has
been — nothing.

Upon returning after a year's absence to shops where
they had been set up, they had disappeared, and the same
answer was received as the reason for their removal.

As nearly all the characteristics presented so far apper-
tain mainly to the class of ocher known as the " silicate "
or the French and English, more will be said now of the
special characteristics which belong to the other or
argillaceous class — those where the clay base predom-
inates.

Reasons have been given why the silicate ochers were
the best for outside painting, and why they should be
used for that purpose to the exclusion of the clay ochers.
But for distemper or water-color work the French and
English ochers are not nearly as well adapted as the
American clay ochers.

Most people are better acquainted with them under the
name of American ocher than any other. In the markets,
the division of ochers into the silicate or clay classes is
unknown. The French and English or the American
in various grades is all the classification they receive.
To all intents and purposes it really amounts to the same,
as the imported represents the silicate class, and the
American the clay class, because about all found so far
in America partake more or less of this character.

In distemper painting, clay ochers work better. They
cover better, and, what is still more prized, they look better
than the silicate class does; so that what they lack for oil

70 MODERN PIGMENTS

painting becomes their chief redeeming quality in water-
color work.

This class of ocher is very common. It is found in
nearly all if not in every state in the Union. Like the
other ochers, it varies very much in composition. So far,
the best that have been found are mined in Eastern Vir-
ginia on the Appomattox River below Petersburg, and
in the same section at Bermuda Hundreds.

Those Eastern Virginia ochers contain a fair per-
centage of silica in their base, but the alumina predomi-
nates. They carry about 25 per cent of ferric oxide.
Their tone is fair, and they may be said to be the nearest
approach to the imported — many jobbers sell them as
" Rochelle." These represent the better grade of American
ochers found so far.

On the other extreme — in Missouri down on the
Iron Mountain railroad below St. Louis — there are found
numerous beds of ocher. The remarkable peculiarity of
these ochers is the enormous quantity of ferric oxide
they carry. Some samples analyze as much as 85 per cent
ranging down to 20 per cent. A fair average for that
section will be more than double that of the imported
class. But what the oxide of iron makes up in quantity
it seems to lose in quality, the tone being universally
poor.

Their chief use so far has been found in the burning
of them into a red ocher and in compounding them with
talc in the making of a cheap Venetian red or rather
mortar color for which they are excellent, being so strong.
Enormous quantities are sold for that purpose alone.

Some of these very strong American ochers are also
compounded with ground talc, gypsum or silicate earths;
some being sold as French and English, but the bulk
going under the American name.

YELLOW PIGMENTS 71

Most of the American ochers are semi-transparent, and
but for their tones could be classed with perfect propriety
with the siennas. Some which do come nearest to them
are so classed and sold as American siennas. This trans-
parency is not apparent in distemper painting, but it
becomes decidedly objectionable for oil painting, even
when compounded with silicate earths, and thus rendered
unobjectionable in all other respects.

In addition to the natural ochers, tons upon tons of that
pigment are made artificially. When a good quality
of ferric oxide is used as the coloring agent, and a right
base selected to hold it up just right, the product can
hardly help being a good one. There surely cannot be
any good reasons given why an excellent artificial ocher
should not be made as well as an artificial Venetian red,
which these all are. What is said under the heading of
that pigment regarding preparation will give the reader
an idea of how these artificial earths are produced and
prepared for use. There is this difference, however, that
in the case of ochers no calcination is necessary — all that
is needed is mixing and triturating. The base is usually
either china, clay, talc and silicate earth in such propor-
tions as best suit the compounders.

The great trouble heretofore has been in the finding of
an hydrate-ferric oxide of sufficient richness to compete
with the French and English imported ochers. So far,
all these artificial ochers have had a lame side in that they
are all too transparent in oil to be palmed off as genuine
French ocher upon the expert ones at least.

For all that, the French and English ochers are silicious;
they are very opaque, much more so than any sample of
American containing twice the quantity of coloring matter.
It looks as if the atomic formation of the hydrate-ferric
oxide from over the water was somehow different from

72 MODERN PIGMENTS

that produced on this side of the big pond — or is this due
to the forms of atoms in some of the bases? There seems
to be an opening here for scientists to investigate.

This kind of transparent ferric oxide appears to be
found in Italy, as many of the Italian siennas contain
twice as much as many of the French ochers, and yet they
are very transparent for all that.

As soon as the proper hydrate-ferric oxide can be
found or artificially produced with as good tone as that
in the imported ochers and as opaque, so that they can
be duplicated at will here, there will be as little French
and English ochers imported as there is now of English
Venetian red. In all likelihood it is only a question of
time when this will take place. All signs point that
way now, and the painter will gladly hail the day when
he can depend to a nicety upon the uniformity and exact
composition of his ochers.

Some of these artificial ochers that have been very
carefully compounded, can be relied upon as being very
superior for outside painting to those that are mined
and that are of uncertain composition. Samples which
were examined and tested show up nearly as good as
many that are imported.

As ocher is the most important of all the colored earth
pigments to the painter, no apology is needed for having
given so much space to its consideration.

CHAPTER VI

CHROME YELLOW

YELLOW PIGMENTS (Continued)

General Remarks Concerning Them.

THE chrome yellows follow the ochers in the list of
yellow pigments, and rank next to them in usefulness and
importance to the painter.

These yellows are all chemically made in color works,
and are found of various tones covering the whole range,
from a deep orange bordering upon a true red to the
lightest of the canary yellows.

Commercially they are known as "canary yellow,"
which is the palest; "lemon yellow" comes next to
that in paleness ; " medium chrome yellow " is the neu-
tral chromate of lead, and its shade borders neither
towards the orange nor the lemon. It is neutral in this
respect as well as chemically. "Orange chrome yellow"
runs in a variety of shades from a very pale tinge of
that color to a deep — almost scarlet — shade of it.
Some manufacturers make it up in three shades,
which they mark as "pale orange," 'orange," and
"deep orange."

The medium chrome yellow is the only one of the whole
range that is the true "chromate of lead." The varia-
tions from it are due to the addition of other substances
added purposely to produce them. So the medium or
neutral chromate of lead, is the base, or standard, from

73

74 MODERN PIGMENTS

which all the others are mere variations. For this reason
its character will be the first one considered.

MEDIUM CHROME YELLOW
Its Characteristics, Chemistry, and Manufacture

Chrome yellow has been known under various names
for over a century. As its name indicates, it is derived
from chromic acid and a lead base.

It is easily obtained as a precipitate by simply making
solutions of the acetate or of the nitrate of lead, which
are soluble in water, and of bichromate of potash, and
pouring the two solutions together in a settling tank.
The chrome yellow will instantly precipitate.

Color manufacturers, however, make it from white lead,
as it is more economical to produce in that way. This
being insoluble in water, requires more manipulations
and boiling. The proportions used are about four pounds
of white lead to one of the bichromate of potash.

CANARY AND LEMON CHROME YELLOW
Manufacture

The lighter shades of chrome yellow are made in
precisely the same manner as the ,neutral chromate
of lead or medium chrome yellow, with this difference:
lead sulphate or sulphuric acid must be added to
the white lead and bichromate of potash. According,
therefore, to the quantity of the sulphate of lead added,
will be the canary, lemon, or intermediate light shades.
The more sulphate of lead that goes in the mixing liquids,
the lighter will be the shade; the less of it used, the nearer
will it approach to that of the medium chrome yellow.

Sulphate of lead is a legitimate component part of a
pale chrome yellow, however much of an adulterant it

YELLOW PIGMENTS 75

may be when added to an already made and precipitated
medium chrome yellow or an orange shade where it has
no business to be, and where, if found, it is a sure indication
of adulteration.

The sulphate of lead must be added before the precipi-
tation of the solutions so as to produce the lighter shades,
as it combines with them then, which it will not do if
added afterward.

Sulphate of lead is frequently used as an adulterant
of medium chrome yellow by simply mixing the two by
trituration. In such a mixture the color of the medium
yellow is not changed.

Chemists who are not familiar with this fact, and who
have not made the study of paint-making a specialty,
frequently make queer mistakes in their analysis. They
know that chrome yellow is neutral chromate of lead, so
that when the lighter samples of chrome yellow are handed
to them for analysis they are sure to call the sulphate of
lead they are bound to find in it an adulterant, not know-
ing enough about color-making to make the proper allow-
ance for the difference in the shade between that and the
medium. It is only when found in a medium chrome
yellow, where it has no business to be, that it can be
considered an adulterant.

As these light shades of chrome yellow vary, so much, it
is impossible to give the exact amount of sulphate of lead
they should contain.

Alum and barytes are. sometimes used to lighten the
tones, but principally as adulterants.

ORANGE CHROME YELLOW
Manufacture

Orange chrome yellows are the opposite of the lemons.
It has been shown that in the lemon and canary chrome

76 MODERN PIGMENTS

yellows, the change of tone from that of the medium was
due to the addition of an excess of acid in the form of
sulphate of lead or sulphuric acid.

In the orange chrome yellows, the deepening of tone
and reddish hue is due to an excess of alkali from the use
of some caustic substance. It may be obtained in many
different ways, but, after all, the difference is in the caustic
substance added to the white lead and bichromate of
potash. As stated under the lemon yellows, they must
be added to the chromate of lead, or rather to the
solutions of chemicals which are equivalent thereto,
and the whole precipitated together. The alkaline
substances mainly employed for this purpose are
caustic soda or caustic potash. The greater the quantity
of these used, the redder will be the tone of the orange
chrome yellow.

In an analysis of orange chrome yellow there will be
found, besides chromate of lead, either lime, soda, or
potash, according to which of those substances was used
before the striking of the precipitate. Therefore, accord-
ing to the quantities of the alkali, the various hues and
shades of orange are produced from the faintest tinge of
orange to those of near approach to a fiery red. There
can be no formula given of the proper amount to use for
the producing of any given shade. The manufacturers
hardly ever strike duplicates of any shade, but produce
hundreds which are not alike. They do grade and mix
many together which will give a fair average for the
standard they have adopted for the required shades of it.

Properties and Uses of Chrome Yellow

Chrome yellows of all shades and hues have about the
same general characteristics and properties, qualities and
defects. It is proper, therefore, to bunch them together,

YELLOW PIGMENTS 77

and to review them under the general head which is the
common property of all.

From their composition, one may well surmise that
they are hardly fit to be used in distemper or water-color
painting owing to the liability of their chromic constituents
of losing their oxygen and of thus becoming changed into
the lower oxide of chromium, which is greenish. The lead
also is subject to the attacks of sulphureted-hydrogen
gases which turn it into a black sulphide. It must be
easily seen by any one that great risks are run when they
are used in water colors for interiors, about the only
place where water colors can be used. When used in oil,
they are protected to some extent by the linseed oil with
which they are mixed, but in water colors there is no
protection whatever against deleterious attacks. -

In oil, however, there are but few colors which the
painter or decorator could find more useful than the
chrome yellows. While not absolutely unfading when
mixed with oil or varnish, in those vehicles the color
remains a reasonably long time before changing to such
a degree as to be disagreeably noticeable.

The range of tints obtainable from them covers the
whole field of yellows and red yellows, which are easily
made and at a very moderate cost.

There is one thing that is sure : There is nothing in the
whole field of pigment that would replace them, let them
be good or bad. It is true that some very few tones could
be made from combinations of other pigments, but at a
greatly increased cost only, almost prohibitive for general
house painting, and nearly all these substitutes would be
much more subject to fading than the chrome yellow itself.
With all their defects, — and it is admitted that they have
many, — they stand high above every other pigment pro-
ducing the same range of color. They will continue to be

78 MODERN PIGMENTS

used until something better is discovered to replace
them.

There are many fancily named yellow colors upon the
market, usually with a proprietary name. They are
mainly prepared for the carriage trade. Most of them
are chrome yellows of peculiar shades.

The fancy names sometimes mislead the uninitiated into
the belief that they are not chrome yellows. This belief
is dangerous, as it may lead one into using those yellows
upon work where chrome yellow should not be employed,
the workman thinking that they are not subject to the
same vicissitudes. With a knowledge of their real char-
acter, such mistakes need not occur.

Chrome yellows are extensively used for all kinds of
painting. The carriage, car, and implement trades use
them in enormous quantities as well as the house painter.

Decorators and artists are the ones who are the most
likely to have trouble with them. They are the only ones
who need have any misgivings regarding their use. They
know that even when mixed with oil, the chrome yellows
are not to be depended upon for use in interior work.
They are therefore warned to be shy of them, substituting
other yellows as far as they can.

BARYTA LEMON YELLOW

Properties and Uses

This is a distinct color from lemon chrome yellow.
It contains no lead in its composition, baryta being the
base of it. It is by far the most permanent form of that
color.

It is made by mixing solutions of neutral potassium
chromate and of barium chlorite; both solutions having
previously been heated to 100° C. It precipitates as all

YELLOW PIGMENTS 79

others made by mixing solutions having an affinity for
each other.

Unlike the lead chromates, it does not blacken by con-
tact with sulphureted-hydrogen gases, that lurking
enemy of interiors. It may also be mixed with impunity
with any of the other permanent pigments.

This yellow is of great use to decorators and artists,
more so to them than to the general house or carriage
painter, because it has not so much opacity in oil as the
chrome yellows, on account of the transparency of its
base.

It possesses one of the defects which is also common
to the chromates of lead. It loses some of its chromic
oxide and becomes greenish in hue.

Adulteration in Chrome Yellows

To detect adulteration in chrome yellow is an easy
thing. It can be done by a very simple operation, which
while it is not a scientific one, and while it gives no indi-
cation of the nature of the adulterant, is nevertheless
very effective. By its use, any one can readily deter-
mine for himself whether a given sample of chrome yellow
is pure or not. This, after all, is all that either a painter
or a dealer cares to know about a color anyway. The
test gives approximately the percentage of adulterant
contained in the color under examination. Its lameness
is that the nature of the adulterant is not revealed. That
requires a chemical analysis. As this test is applicable
to many other pigments, especially to all made from chem-
icals and which possess a recognized standard of purity
and composition, and as it is also, in part at least, appli-
cable to many of the earth colors in so far as it will fre-
quently help one in determining the value of these, the
manner of making this test is minutely described, so that

80 MODERN PIGMENTS

hereafter, when there may be occasions for reference to be
made to it, the reader can turn back to the explanation
given here, should he require to have his memory
freshened up as to the "modus operandi" of making the test.

The Scale Test for Adulterants in Colors

As a detector for adulteration in colors, the test which
is about to be described is applicable in full only to those
manufactured in color works from well-known formulas,
and which, if pure, should contain a known amount of
coloring matter. That is what gives them their com-
mercial value. This test only becomes a side issue with
colors whose chief value consists in their fine
tone and their brilliancy, as with most of the earth
colors. Even with these, the test will serve to deter-
mine which is the more valuable between two
samples of equal tone and brilliancy in determining
that containing the greatest quantity of coloring
matter.

Every one interested in colors, be he dealer or painter,
should possess a pair of fine scales for testing. These
should be very sensitive ones, very accurate, and able to
weigh with precision as small a portion as a quarter of a
grain, or at least a centigram. Such scales need not
necessarily be expensive. The knocked-down army
surgeon pocket scale is good enough, if one does not care
for style. That has a little flat box with a drawer
fitting inside. This box serves as a pedestal, and the
drawer as a receptacle into which is packed away the
standard that screws into the pedestal and across which
the arm of the scale is pivoted and supports the two
platters, pans, or balances which receive the substances
to be weighed. They can be put up and taken apart
in two minutes, and will answer every purpose.

YELLOW PIGMENTS 81

The testing in substance is done in the following man-
ner. Two samples of a given color are procured — one of
which is of known purity, to serve as the standard in
judging the others. A very good plan is to take tubes
of, say, Windsor and Newton's artists' colors, or any other
make whose purity is as well established. The above
firm's make is named because they are universally known
and acknowledged as standard in both quality and purity.
A sample tube of all the principal colors should be found
upon the shelf of every paint shop and of every paint
dealer. The cost is very moderate.

It stands to reason, that if a person should take, say,
one pound of color ground in oil, and add thereto twenty-
five or fifty pounds of white lead, and that after triturat-
ing them properly they will make a tint that should be
equal in strength or depth of tone and in its quality to
any other sample or samples tested with it if those sam-
ples have been weighed out and treated in exactly the
same way, they will do so if they are pure and unadul-
terated. If, on the other hand, some of the samples do
not give as deep a tint as the standard color, it follows
necessarily that there must be deficiency in coloring
matter.

It is impossible to determine to a fraction the amount
of adulteration contained in the weaker pigment, but one
can make a very close guess of it in this way :

Add enough white lead to the sample which is the
strongest in coloring matter so that its tint will be
reduced to the same shade as that of the weakest; then
reweigh and note the variation. Thus, if one pound of
a certain pigment tints twenty-five pounds of white lead
to a given shade, and in the other, the one pound of the
same color has been able to tint thirty-seven and a half
pounds of the white lead to the same shade as the other

82 MODERN PIGMENTS

has — then the first must have been adulterated with
50 per cent of something that was not coloring matter.
If, instead of thirty-seven and a half pounds, it had
been able to tint fifty pounds of white lead to that
same tint, then the adulterant put into the color would
be equal to 100 per cent. In other words, the
sample contains one half pound of true color and one
half pound of adulterating material, so that for tinting
purposes it is only worth one half as much as the
stronger one.

Some may think that the above is an extravagant
statement to make, even as an illustration to show how
the test works, but it will be found very much below
the truth. This is especially so in the higher-priced
pigments and in those possessing great strength of
coloring matter.

In making tests, there is no need of using any such
quantity of color and lead as was stated in the illustration.
One grain in weight is as good as one pound, or even
better. No weights need be used, as a bit of coloring
matter the size of a pea can be put upon one of the plat-
ters, while another bit of color can be placed upon the
other, and added to or subtracted from until they balance
evenly. Each of the colors to be tested should be put
upon a little piece of paraffined paper about a square
inch in area. That paper will not absorb any of the color
or oil, which can be wiped clean off of it. For accurate
testing, it is better to weigh the colors separately in cen-
tigrams or grains. Next proceed to equal quantities of
white lead of same consistency, placing that also upon
squares of paraffined paper, but larger than recommended
for colors, so as to accommodate the larger bulk of the
lead. These are placed upon the platters and balanced
in the same manner as for the colors by either adding

YELLOW PIGMENTS 83

or subtracting; or, if perfect accuracy is desired, weigh out
twenty-five or fifty grain packages of white lead, one
each for each color being tested.

Have several pieces of glass ready which have been
properly cleaned, and upon one of these place the first
sample, which should be the standard color. Add to this
one of the packages of white lead previously weighed out.
Triturate the color with the lead until the tint is uni-
form all through, using a palette knife for that purpose;
add a given number of drops of oil if needed to help the
mixing, then set it aside.

Proceed to treat the next sample in precisely the same
way, and stand that aside too. If more than two samples
are being tested, keep on treating each in the manner
described.

Now compare each sample with the tint made by the
standard color and note the differences. If each shows
about the same strength in their tints, well and good; the
colors are pure. If, on the other hand, one or more do not
come up to the tint of the standard, there is something
wrong with them. By adding enough white lead to the
standard tint to bring it down to the tint of the next
strongest sample being tested, and weighing each, the
difference between them will give the quantity of adul-
teration contained in the sample.

If more samples than one are being tested at the same
time, proceed to add more white lead to the standard
color; continue adding white lead to the standard to
bring it down to the tint of the next sample in strength,
weighing each time and noting the difference, and continue
doing so in like manner until the standard has been
reduced to the tint of the last or weakest in the lot. This
will give the relative value that each bears to that of the
standard used.

84 MODERN PIGMENTS

Thus if the standard color is capable of producing a
tint from one grain of color added to two hundred grains
of white lead equal to that which sample 1 does from one
grain of color to one hundred grains of white lead, and as
sample 2 does with fifty grains of lead, then if the stand-
ard color can be bought for twenty cents per pound,
sample 1 is worth, proportionately, ten cents. Sample 2
is only worth five cents per pound, because No. 1 contains
only fifty per cent of the coloring matter as compared to
the standard, while No. 2 carries only twenty-five per cent
of it.

In the testing of chrome yellows, samples of different
tones should never be tested together, — for instance, a
very light lemon yellow against a very dark one, or a
lemon chrome against a medium or an orange chrome, or
vice versa. The tints made will be so much different
that it would be very hard if not impossible to judge the
results correctly when placed side by side.

This test usually brings out other valuable points, i.e.,
the quality of the tints made from two or more given
samples. A medium chrome yellow may be nearly pure,
but it may be very poor. Therefore, if the tint obtained
from it is muddy, and that from the standard is bright,
clear, and pure-toned, it follows that the muddy sample
was a badly made chrome yellow, and that, notwithstanding
its purity, it may possibly be of less value than one which
has been adulterated but which is of good tone and well
made. This is a test of quality which is brought out inci-
dentally by the use of the scale test.

The testing of the quality of colors does not require
the scale test, however, as one can ascertain that by the
eye alone. All that is required is to mix some of the
color with white lead to' make a light tint of it. The tint
will speak for itself. The tone of some samples of chrome

YELLOW PIGMENTS 85

yellow may be so poor that the quality can be determined
without disturbing it or even taking it out of the can. As
occasionally it may belie its looks, it is safer to add some
white lead. Then there can be no doubts left in one's
mind.

Color tests made in the above manner are very simple
and convincing ; and the painters or dealers who make a
start in testing the material they use or sell, hardly ever
quit making a regular use of it, thereby gaining an expe-
rience in judging of colors and their values that will be
very profitable to them in after life.

CHAPTER VII

t

YELLOW PIGMENTS (Continued)
GAMBOGE

Properties and Uses

GAMBOGE is seldom if ever employed by the house
painter, but is still used by a few decorators and artists.
Its chief value is as a glazing color; in reality it cannot be
used for any other purpose; some few carriage painters who
do fancy colored painting use it to obtain certain effects.

Gamboge is of vegetable origin; being a gum-resin. It
should never be mixed with other pigments containing
lime or alkali in any form; they would surely darken.

It cannot be safely used as a distemper color, as it
fades rapidly upon exposure to the air and the sun's rays.
Its use even in oil is questionable, but it is fairly permanent
when well protected by varnish.

Its chief use to artists is in the peculiar shades of green
combined with indigo or Prussian blue.

The paint world is likely to keep moving on a long time
after it has been discarded, as its place can be advan-
tageously taken by Indian yellow or aureolin.

AUREOLIN, OR COBALT YELLOW

Properties and Uses

This is another yellow pigment which will hardly ever
trouble the ordinary house painter. A few decorators use

86

YELLOW PIGMENTS 87

it sparingly. It is used principally by artists in water-
color work. It is transparent and rich-toned, and is
superior to gamboge for glazing purposes.

It is a non-drying color in oil. When prepared for use
in that vehicle it will prove more or less troublesome. If
it can ever be prepared in such a way as to make it part
with its water of hydration, — in other words, rendered
anhydrous at a reasonable cost, — it may then become a
very popular color not only among decorators but for
carriage and the allied trades as well as for any other
kind of painting. As it is now in its hydrated state, it
soon loses its rich tone and assumes a dirty appearance.
Hydrochloric and nitric acids do not seem to affect
it to any extent, but ammoniacum sulphide destroys
its color at once, and sulphureted hydrogen gases soon
darken it.

The future may give us the anhydrous aureolin at a
reasonable cost. When this is accomplished, it will be a
great addition to the list of yellow pigments. In that
form, it dries readily when mixed with a siccative oil, and
that is the form in which artists now use it for oil paint-
ing. As they use it in small quantities, it does not make
such a big hole in their bank account as it would were they
to use it in quantities as the house painter or decorator
would.

INDIAN YELLOW

Properties and Uses

This pigment is of animal derivation, but in reality it
is of vegetable origin obtained through animal agency;
it is found in their urine. In Bengal, cows are fed upon
mango leaves, and the urine of cows so fed becomes im-
pregnated with the coloring matter which forms Indian
yellow.

88 MODERN PIGMENTS

Church says of it: "It generally occurs in the bazars of
the Punjaub in the form of large balls having an offensive,
urinous odor." Indian yellow is an impure salt of
(magnesium) euxanthic acid. The essential part of it is a
compound containing 4.5 per cent magnesia, 18.7 per
cent water, 78.7 per cent euxanthic anhydride; but this
substance is always associated with various impurities
both mineral and organic, even in the most carefully
purified samples of prepared Indian yellow. The pure
magnesium euxanthate is represented by the formula
C19 II16MgOn5H20.

" For artistic purposes the crude imported Indian
yellow is thoroughly powdered, and then washed with
boiling water until the liquid filtered from it is no longer
colored; a brown impurity and much of the evil smell are
thus removed. The color of the washed product is
enriched by leaving it in contact for a day or two with
a saturated solution of salammoniac and then repeating
the treatment with hot water. Thus prepared and
purified, the pigment presents a translucent orange yellow
of great depth and beauty. Ground in oil, some specimens
remain practically unchanged even after long exposure
to sunlight, any darkening which they show being due to
either imperfect purification or to change in the associated
oil. Such change is reduced to the minimum if poppy-
seed oil is substituted for linseed oil, or if the latter be
previously treated with manganese bo rate."

As a water color, Indian yellow is also very useful. It
is not absolutely permanent, but fairly so for a water-
color yellow. Its fading, being very slow and gradual, is
not noticed readily.

It can be mixed with any of the permanent pigments,
and sulphurous compounds do not affect it injuriously.
It is too expensive a pigment to ever become extensively

YELLOW PIGMENTS 89

used by ordinary painters, but it deserves to be more
than it is by decorators, scenic painters and artists,
also by the carriage trade as a glazing color. It does
all that gamboge is expected to do for that purpose, and
much more in that it remains permanently.

NAPLES YELLOW

History and Chemistry

The early history of this pigment is very obscure. It
was first brought «to notice in a commercial way by the
Italians, and imported from the city of Naples in Italy
into England, and it was named after the city of its
exportation by the English importers. The Italians
themselves know it as yellow or gialloline. It is a
compound of oxide of lead, antimony and zinc. Twelve
parts of the metallic antimony are calcined in a
reverbatory furnace with eight parts of red lead and
four parts of the zinc. These mixed oxides after being
well rubbed together are fused, and the mass broken into
a fine powder.

The hue is rich, fresh, and brilliant. There is a con-
siderable quantity of this yellow placed upon the market
that is made simply by mixing cadmium yellow or a deep
cadmium with the white oxide of zinc. This, while it
makes a good imitation of Naples yellow, is not it, for
all that it may look like it.

While it is only of comparatively recent date that it
has come back to us, the first notes of its appearance only
dating back to the middle of the sixteenth century,
it was known to the ancients for many centuries previous
to that time. It was used in the enameling of brick in
Babylon 700 years B.C., and the Persians used it also
in the enameling of their pottery.

90 MODERN PIGMENTS

It has been used extensively by artists, decorators, sign
and carriage painters, and is still used to a certain extent
by some of all these to-day, but not nearly to the same
extent as it was fifty years ago. The chrome yellows
have made quite an inroad upon its use, and have dis-
placed Naples yellow in many shops.

Properties and Uses

Naples yellow is fairly permanent, but, like all com-
pounds containing lead, it is blackened by sulphureted -
hydrogen gases. It is also darkened by contact with
iron, zinc, pewter, tin, and many more metals, to the
extent that even an iron palette knife should never be
used in triturating it, but a bone one should always be
employed for this purpose.

Naples yellow should never be used in combination
with certain organic pigments as cochineal, the various
yellow lakes, indigo, etc. Naples yellow is worthless as
a water color, as it is very fugitive when left unprotected
by the enamel formed by the drying of linseed oil or
varnishes.

It is gradually becoming displaced by the chrome
yellows and ochers, or combinations of these two, and
with no serious loss. The Naples yellow tone can be
readily imitated; and in this one instance at least the
imitation is superior to the original, — it is more perma-
nent.

DUTCH PINK

Character and Preparation

Dutch pink has many synonyms, i.e., yellow lake,
Italian lake, quercitron lake, brown lake, yellow
madder, and a host of others under which it is known in
various sections, especially in England, where it is

YELLOW PIGMENTS 91

unknown under the American cognomen of Dutch pink.
As under this name only is this pigment listed in pigment
catalogues in the United States, and as this is recognized
by all color makers in their price lists, the name is used
here in preference to any of the synonyms. Why
it should be called a pink (?) when it is not a pink,
but a yellow, is one of the conundrums that must
be passed around to some one else for a satisfactory
explanation.

Dutch pink is of vegetable origin, and it can be and has
been prepared from various sources, but it is now chiefly
derived from quercitron, a product extracted from oak
bark. Our black and red oaks contain the greatest per-
centage of it, although it can be obtained from the bark
of white oak also.

A decoction of the bark is made by boiling, and the
quercitron is precipitated by pouring into it while hot
a solution of alum and dilute ammonia.

A richer-toned pigment is produced by using dilute
boiling sulphuric acid instead of water in extracting it
either from the ground bark or alburnum.

In former days much of the Dutch pink was obtained
from various species of buckthorn and of the Rhamus
family of shrubs.

Properties and Uses

It is possible that the variety of names under which
Dutch pink is known may have been given to the various
extracts at some time or other to note some slight varia-
tion of tone in them. This is more than doubtful, as it
is next to impossible to ever find any two lots of it that
are just alike in this respect. It is useless to keep up a
confusing nomenclature, and all lakes of the same extrac-
tion should be classed together and known by one name

92 MODERN PIGMENTS

only. When an Englishman calls for any of the above-
named lakes, the dealer will be perfectly safe in giving
him Dutch pink instead of them.

Dutch pink has but little permanency when used in
distemper for wall coloring, and yet, strange to say, that
is the purpose for which it is mostly used. Why that is
so is one of the unsolvable mysteries.

Its use in the United States is confined to a few sec-
tions where the traditions of its usage have been handed
down and inherited without the worth of the legacy
having been investigated.

In oil it is a bad drier, and while it is more permanent
in that vehicle than in distemper, — because of the pre-
serving influence exerted upon it by the linseed oil, — it
is insufficiently so, and there is no need of one taking
unnecessary risks by using it. As a glazing color it is
all right while it lasts, and it is used for that purpose in
some carriage shops.

CADMIUM YELLOW

Chemistry, Properties, and Uses

This pigment is chiefly useful to the artist and to the
decorator. When properly prepared it is fairly perma-
nent, but as its cost is relatively high and must ever
remain so, for this reason if for no other its use will never
become popular with the house painter. As its name
indicates, it is a product of the metal cadmium, a near
relative of zinc. It is a sulphide of cadmium. The pro-
cess required for its manufacture and preparation is
too intricate and too lengthy to relate in a treatise
of this kind, however instructive it might be. Its use
is too limited to warrant giving it the necessary space.
It runs from a yellow with a slight orange streak in it to

YELLOW PIGMENTS 93

all the intervening shades from the lightest to the
deepest orange.

It possesses some very good traits. One is that of
preventing the injurious action of sulphureted-hydrogen
gases upon white lead when it is mixed with that.

On the contrary, again, such colors as Paris green are
ruined by contact with it, and so are all others which are
incompatible with a sulphide.

The cadmium yellows work well in either oil or dis-
temper, and make beautiful tints with white lead. Some
of these shades resemble true Naples yellow, and as they
are more permanent, they are often substituted for it.
When cadmium yellow is used in oil, this should be made
siccative by the addition of driers.

It is, therefore, chiefly used by decorators for interior
work. This is more liable to attacks of sulphureted-
hydrogen gases than outside painting, and as the chrome
yellows are badly affected by them, and therefore unsafe
to use, cadmium yellow's chief utility is to replace them
under these conditions.

KING'S YELLOW (ORPIMENT)

Chemistry and Characteristics

This pigment is the yellow arsenic sulphide, and on
account of its poisonous character should be discarded.

The only excuse for listing it at all is that, under its
heading, a note of warning might be given against its
use. It is listed in some of the artists' goods catalogues,
and some reference is made to it in some of the past
paint literature.

Under its best aspects it has little to recommend it,
and when its poisonous character is taken into account,
no one need have anything to do with it. At best, it is

94 MODERN PIGMENTS

quickly destroyed by light, and while it possesses a beau-
tiful hue, that fades away so quickly as to render it
worthless.

It was used rather extensively at one time, especially
in the latter part of the eighteenth century and at the
beginning of the nineteenth. It has all disappeared from
the paintings of that period which have been preserved,
and it is but seldom used to-day even by artists.

The above ends the list of yellow pigments. It is true
a few others are sometimes found listed in artists' cata-
logues, such as Mars yellow, etc., but a close inquiry will
develop that they are simply ochers or compounds of
colors which have been described.

The endeavor should be made to keep the list of pigments
to the least possible number and to simplify the nomen-
clature by eliminating from the list all pigments of the
same nature sold under various names, thus creating a
false impression in the minds of many that they may
have different properties.

Many of the yellows which have received a description
in this treatise will be found of little benefit to the gen-
eral painter, but most are of use in certain special kinds
of work which are named. The very knowledge that
they are not adapted to his work is of value, as it may
save him money in the making of useless experiments.
The aim has been to give warning of all the defects as
freely as the giving of praise to the good qualities of each
when that was really deserved.

CHAPTER VIII

RED PIGMENTS

VERMILION

History and Provenance

QUICKSILVER VERMILION is usually understood when the
word vermilion pure and simple is used alone. All others
have some descriptive name added to indicate their
character.

Quicksilver vermilion is commonly listed as English
Vermilion, and the name has come to have that signifi-
cation to the paint trade of the United States.

Vermilion is found as a natural product in the shape of
and under the name of cinnabar in various parts of the
world. It is most abundant in China, and has been found
and used in that country from time immemorial. In America
it is also found plentifully in the New Almaden mines of
California. In Spain, in the old Almaden; in short,
wherever quicksilver is mined, there it is usually found.

It is frequently obtained in masses which vary very
much in color, ranging from a light crimson through the
scarlet red range of shades to a dark slate gray. These
masses after having been powdered become scarlets or
reds of various hues.

The native vermilion or cinnabar is usually singularly
pure and free from foreign matter, and the impurities
seldom amount to as much as one per cent of its weight.
It is friable, readily pulverized.

95

96 MODERN PIGMENTS

Chemistry and Manufacture

Cinnabar is a native sulphuret of mercury, and it is
composed of 86 parts of mercury united to 14 parts of
sulphur.

It is most probable that it was used at very remote
periods in such decorations and art as then existed.
Theophrastus names two varieties of cinnabar as being
known to the Greeks. Pliny and Vitruvius also mention
it in their writings.

Vermilion can be made artificially by following the
formula nature has adopted to produce the native cinna-
bar. The vermilion of commerce is nearly all made
artificially.

The process of manufacturing it, while it may be called
a very simple one, becomes rather complex before the
end is reached.

The combination of quicksilver and sulphur is readily
accomplished, it is true, but the result is a black mass
known as Ethiops. This is the black sulphuret, and it is
identical in chemical composition to the red, with this
difference — that the black is amorphous, while the red is
crystalline.

There are two processes of manufacturing vermilion
artificially : one is known as the dry, and the other as the
wet.

In the dry method of manufacturing it, the mercury
and sulphur in the proportion of 21 parts of the former to
4 of the latter are agitated and mixed in a revolving
cylinder. The resulting black ethiops is then submitted
to a process of sublimation in vertical cylinders, over
which are placed connecting receivers. Upon being
heated sufficiently, the sulphuret of mercury sublimes
as cinnabar near the retort's heads; the finer quality is

RED PIGMENTS 97

found the farthest away, and the poorest the nearest, as
that contains a quantity of free sulphur. It is afterward
separated into various grades.

The vermilion is mixed with water to a stiff paste, and
thinned with a solution of caustic potash and nitric acid,
and thoroughly washed with boiling water. There are
other processes of manufacturing vermilion, but they
differ but little in their essentials from the above, and
therefore will not be discussed. All have the same object,
— the conversion of the black amorphous sulphuret into
the red crystalline form by sublimation. Some add one
per cent of sulphide of antimony with a view of enhanc-
ing the beauty of the product.

By the wet method, the processes are much simpler,
and there are a number of different ones in use. The
simplest is that of Bucholz: Take four parts of mercury
and one part of sulphur, which are digested together in
six parts of water. Potash is added as required. The
longer the heat is continued, the stronger and more car-
mine will be the product. When the desired color has
been produced, the vermilion is thrown into a vessel of
water and washed until all the sulphuret of potash has
been removed. The color of vermilion is not changed
when moistened with nitric acid.

Carmine is sometimes added to the crimson varieties
of vermilion to enhance the tone. The Chinese vermilions
are usually of that shade. They are frequently adul-
terated with carmine. It can easily be detected by putting
a small pinch of it upon a piece of blotting paper and
wetting that with a few drops of strong aqua ammonia.
If adulterated, a crimson stain will appear upon the paper;
otherwise it will not be affected.

Vermilion that is prepared from the native cinnabar
is said to be more permanent than that which is made

98 MODERN PIGMENTS

artificially, but one should not adopt the statement
implicitly.

Characteristics and Uses

When vermilion is used under proper conditions it is
fairly permanent, otherwise it is not.

As to the darkening of vermilion, the common complaint
made against it, one must bear in mind that the natural
form of the sulphuret of mercury is that of the black
ethiops or amorphous, while that of the red or crystalline
is a forced one. There is a constant return from the
crystalline to its natural amorphous condition, hence
comes the gradual darkening of this beautiful color when
left to the direct action of light and air. Even when not
directly exposed to the action of the elements, the gradual
change takes place, but in a much slower way.

Vermilion prepared by the wet process is usually more
crimson than that made by the dry, and this is more
likely to fade than the scarlet-toned ones. Another
peculiarity of the wet process and of all crimsoned -toned
vermilions is that they do not have as good a body or are
not so opaque as those of a scarlet tone. Another pecu-
liarity of vermilion is that the finer it is ground, the paler
it becomes and the quicker it will fade. As a water color,
when it is left unprotected from the influences of air and
light, vermilion is absolutely unreliable under such cir-
cumstances.

In oil or varnish, it is fairly permanent ; and when the
painting has been done on a proper ground with the right
vehicles, and afterward well varnished over, it will not
change readily, and may be called " unfading," com-
paratively so at least.

Linseed oil itself, in its ordinary condition, is not a
good medium for it. Gold size, japan, or a good varnish

RED PIGMENTS 99

are much better for that purpose. This is the principal
reason why the coach and car painters have nothing but
praise for it and are so successful in its use, while the house
painters, who are used to mix their colors differently, and
who also in all probability are not so familiar with the
peculiarities of that color, usually have little good to say
of it. The latter bring in nearly all the complaints against
it.

The genuine simon-pure vermilions can be safely used
with most pigments. It is only when they contain free
sulphur, as in the lower grades, that there is any danger
of mixing them with other pigments.

Vermilion, owing to its heavy weight or density, pre-
cipitates readily when mixed in liquids, therefore it is
best to buy it in a dry state. It is found ground in oil
or varnish in small cans; in reality it is not ground in
them, — it is only mixed into a paste with the liquids.
This the painter can do as well for himself at the shop
without any waste, as he need mix only as much as he
wants. The grinding would destroy the color, and manu-
facturers or grinders are too smart to want to do that.
The coarser the atoms of vermilion, the richer and
more brilliant will be the tone. The above statement is
not only true of vermilion, but also applies to all colors
having a crystalline nature.

A crimson vermilion is usually more transparent than
the pale or finer ones, the crystals of the deep crimson
variety being coarser. To this are partly due its greater
transparency and brilliancy. The unbroken crystals
give a reflection and depth to the finish which is remark-
ably beautiful. It is not so fine nor as opaque as the
pale vermilion, but richer toned. But it is not so deficient
or transparent but that, over a proper ground, it will
cover well in one coat.

100 MODERN PIGMENTS

The pale varieties, being finer and more opaque, are the
ones commonly used for lining or striping, and the only
red that can be used to make a solid-looking stripe in one
coat over black.

IMITATION OR VERMILION REDS

Manufacture and Preparation

The vermilion reds, as the imitation vermilions are
now called, are fast encroaching upon the domain of the
genuine or English vermilion, as quicksilver vermilion
is usually known in the United States. It is really won-
derful to note how much progress and how many improve-
ments have been made in the manufacture of these reds
within the past fifteen years. All but the opacity of the
genuine pale vermilion has been attained in them and
reproduced in the imitation. In some respects, as in per-
manency, some of these are even superior to the genuine.

This progress is mainly due to the discoveries in the
making of alizarin and other high-grade coal-tar prod-
ucts. Some were formerly obtained from madder root
at great cost; and later the introduction of the para-
diazo reds has completely changed the output in that
class of goods.

A short review will be made of the different grades of
vermilion reds.

Every color manufacturer has his own peculiar way
of handling or preparing vermilion reds, the usefulness of
which he claims to be "just a little bit" ahead of
that of his competitors, and to protect which he gives
to his products a proprietary name.

The multitude of names for these reds has been the
cause of no end of worry to painters and paint men who
are not familiar with them. There can be but little doubt

RED PIGMENTS 101

that in the recent past, when every thing in the manu-
facture of vermilion reds was new and really in an ex-
perimental stage, there was considerable difference in the
output of the different manufacturers of these reds. Some
seemed to have the coloring matter much better fixed
than others; but the field of search has been an open one
to all, and what with the aid of chemistry and of "catch-
ing on" combined, the competing ones have not been
slow to note any improvement in the other fellow's output
nor in getting acquainted with it in some way or another.
To-day the man who has not been able to keep up his end
with those in front, has had to abandon the field or
content himself with the making of inferior goods only,
and he is known to the trade.

The result of this competition is that now one can
safely say that all prominent color makers make good
goods. All make certain lines of low-grade goods, as
some trades want them. These are usually colored with
a cheap aniline color thrown upon a cheap base. But as
long as there are large buyers who are not willing to pay
more for a vermilion red than for what a good ocher sells
at, they will be catered to. These cheap reds also serve
as a type to compare the crude efforts of the beginning
with what has now been achieved. They fairly represent
the first attempts to make imitation vermilion some
thirty years ago.

The vermilion reds are all made upon a base which is
dyed with a coloring agent. The coloring agent is good
or poor, an expensive or a cheap coloring coal-tar dye
which may be worth 25 cents or $5 per pound. In this
as well as in every other instance, the better dye costs,
the most money.

White lead is the usual base taken to make the crimson
varieties of vermilion reds, as it absorbs a much larger

102 MODERN PIGMENTS

proportion of the dye stuff than does orange mineral
the base which is mostly used for the scarlet varieties.

The two above-named bases are used for the best
grades of vermilion reds only, and intended for vermilions
which are to be brushed out or painted over by hand upon
the work. But there are many other bases used, to
lessen the cost and for other and legitimate purposes;
for instance, as where the reds are to be used for dipping.

Such heavy-bodied bases as white lead or orange min-
eral would be entirely unsuited for such a purpose. Their
heavy weight would soon precipitate them down to the
bottom of the dipping tanks. For this purpose the
lightest-weight base that it is possible to find is the one
which answers the purpose best of any, and will remain
in suspension in the thinning liquid a much longer time
than the heavier bases without settling down to the
bottom.

Whatever the base may be, or the character of the
coloring agents used for their dyeing, the process of
making the vermilion reds is a simple one. There can
be but little difference in the manner of the handling of
the Various manufactures. The claims of superiority,
etc., made by some on the strength of these, must be
looked upon with suspicion. The superiority rests alto-
gether upon the quality of the dye, and of course proper
regard to fixing it.

The base and coloring dye is agitated in large vats and
allowed to settle, and after the supernatant liquid has
been withdrawn, the pulp color is placed upon filtering
cloth and covered with the same. It is then put in the
filters, where the liquid is pressed as dry as possible. The
flat cakes are then taken to the dry-house and dried out
bone hard, after which they are pulverized and are ready
for market.

RED PIGMENTS 103

Properties and Uses

For distemper painting, the cheaper vermilion reds
are of little value. The coloring matter fades rapidly
away when exposed to sunlight, as it is unprotected
by varnish. The good reds stand much better,
but they will darken and become dingy, losing the
charming rich tone which they possess in varnish.
The cheap kinds usually bleach white if made on
a white base; even those made on an orange mineral
base will become of a light pink, eventually changing
to white. It is therefore unadvisable to use such in
distemper.

The vermilion reds which are designated as permanent
reds and sold by manufacturers, are usually so to a good
degree, and are really more so than English vermilion,
especially the crimson-toned ones if they are used under
varnish, and the varnish coating is renewed as it decays
away. This is especially true of the Para red.

Coach and implement manufacturers use enormous
quantities of those reds. Every country repair shop
keeps some in stock. Japanning works use them and
they may be said to have displaced the genuine vermilion
or nearly so.

For striping purposes they have so far been unable to
replace the pale English, as they do not possess the same
degree of opacity. In this one instance, the genuine is
likely to hold its own.

Ammoniacal vapors are injurious to these reds, and they
should never be used where they are likely to be exposed
to their influence. Nor should they be used for the mak-
ing of tints. They are injuriously acted upon by most
pigments they come in contact with. They should
be used alone, just as they are.

104 MODERN PIGMENTS

They are usually ground fine enough for use, ready
for the thinner or vehicle that is to serve for their
application.

They are also found in the supply stores ground up in
oil or in japan. Some manufacturers do not sell their
highest grades of Para reds in any other form, claiming
that they fear a misuse of the dry pigment which
would hurt the reputation of the goods; there may be
something in this claim, but it looks fishy.

AMERICAN VERMILION

Character and Uses

So-called " American " vermilion is not an American-
made quicksilver vermilion, as the name would indicate.
It is not even an imitation of it, and for that reason it is
not classed with the vermilion reds or imitation ver-
milions, nor described under that heading.

It is a dark chromate of lead, of a very deep orange in
tone. It is crystalline in the form of its atoms, and
to this is due its brilliancy. It should not be ground, as
grinding crushes its crystals and destroys its beauty in a
great degree.

Previous to the introduction of the vermilion reds, it
was much more extensively used than it is now by the
implement-manufacturing interests, but to-day on account
of its duller color — which may be called a brown orange
red alongside of the vermilion reds, whose clear scarlet
it lacks — it is very seldom used by them, as these have
entirely supplanted it.

American vermilion is fairly permanent. Instead of
fading, it becomes a darker brown in time. Under the
exposure to sulphureted-hydrogen gases it turns black,
like most all lead products.

RED PIGMENTS 105

It is still used by a very few wagon and implement
manufacturers in combination with red lead, either as a
sort of a trademark to distinguish it from others, or in
mixtures with vermilion reds, as it is thought by some
to prevent the bleaching out of the cheap reds.

CHAPTER IX
RED PIGMENTS (Continued)

* /ry

VENETIAN REDS

History and Manufacture

As the name of this pigment indicates, at some remote
time the Venetians must have introduced it to the world.
It is, or rather was, a natural earth, and red earths vary-
ing greatly in tone are found in all parts of the world. In
Europe, but especially in Italy and near the city of
Venice to which it owes its name, it is plentiful. Similar
reds have been in use from times immemorial in the
decoration of many objects by the ancient civilizations
whose long-hidden remains of art have been brought to
light in the recent past.

All these natural earths of a red tone owe their coloring
matter to ferric oxide, and therefore vary greatly in tone,
in the quality and in the percentage of ferric oxide con-
tained in them. This is to be expected, and it could not
be otherwise. The base or earth upon which the ferric
oxide has become associated varies with each bed from
which it is taken. Therefore there is not and cannot be
any standard whereby to judge the value or purity of
these reds.

The above does not apply to what is now known as
Venetian red, which is made artificially. These arti-
ficial reds can be depended upon, not only as to the
coloring and its uniformity, but also in the quantity

100

RED PIGMENTS 107

contained in a given weight. The late William C. Wilson,
whose name has been mentioned elsewhere, describes its
manufacture minutely in an essay published in Painting
and Decorating a few years ago. The essay is too long
for reproduction in full for the purposes of this treatise,
but the main features of it are contained in the following
description: "Venetian red, like ocher, owes its coloring to
oxide of iron-. Oxide of iron does more for color than any
mineral. "Venetian red is made in various ways. If
copperas be placed in retorts and subjected to a high
temperature, fuming sulphuric acid will distill over and
a red material will remain. This red residue when reduced
to a fine powder by powdering and levigation, becomes
colcothar, crocus or rouge, and is a pure oxide of iron. It
is mixed with gypsum in varying proportions as desired,
or up to a fixed standard established for certain brands.
The so-called English Venetian reds are of this character.
The standard adopted for a first-class article of Venetian
red is about five parts of gypsum to one part of the crocus.
Gypsum is sulphate of lime, and experience has proven
that it is one of the best bases for colors, and that Venetian
reds made from it and crocus are good paints. The
Venetian reds are coarse and require considerable labor
to bring them to perfection. On this account, it has been
customary to consider Venetian red when ground in oil
as a coarsely ground color. Finer grades of red are pre-
pared that are not only finely ground, but are made with
a smaller percentage of gypsum, and then they are known
as super Venetian reds or Turkey reds.

"Gypsum is not alone used as a base for the crocus;
barytes and whiting are frequently used for the purpose.
The great weight of barytes and its little power to absorb
and combine with oil renders it a very undesirable base,
the red so made having none of the durability of the

108 MODERN PIGMENTS

gypsum red. To the paint grinder, it saves a large per-
centage of linseed oil in grinding, and that is the costliest
part of it.

"A gypsum red requires from 25 to 30 pounds of oil to
every hundredweight of the color to grind it — a barytes
red requires only 12 to 15 pounds for the same quantity.

"But this is not all the saving to the grinder, for the
mills will grind nearly twice as much of the barytes reds
as they will of the gypsum reds in the same number of
hours, and the former will look smoother than the last,
and require smaller packages to hold it in.

"Whiting makes a better base than barytes, but it is
still inferior to gypsum, its chief attraction to the
grinder being the smooth-looking paint it makes.

"All reds made by copperas are deep in tone. Certain
ocherous earths are found which on "furnacing" or cal-
cinating will give bright reds, and some of these give very
light shades."

The terms American Venetian reds and English Vene-
tian reds mean very little to-day other than as designa-
tions for the low and high qualities of that pigment.
The better or higher qualities are sold under the name
of "English" Venetian red, and the poorer qualities under
the name of "American."

As good qualities of Venetian reds are made in America
to-day as any that are produced in England, and impor-
tations of this pigment from that country are very much
reduced. The good grades of the reds made in the United
States are branded and sold as English Venetian reds.
The name signifies quality only, and ours of the same
excellence are as much entitled to it as the imported.

Large manufacturing plants exist and have been in
operation for years in Philadelphia, Pa., Worcester,
Mass., and on a smaller scale in other localities.

RED PIGMENTS 109

The so-called American Venetian reds are principally
barytes and crocus mixtures, or a calcined ocher of poor
quality and but one degree removed from a Spanish
brown, much of which is prepared arid marketed from
Baltimore, St. Louis, etc.

Many more pages could be added to the above in
describing the processes used in the manufacture of the
higher grades of Venetian reds, but they are too intricate
and lengthy to be of interest to the general reader, and
would be of value only to the color maker.

Properties and Uses

It is enough to say that Venetian reds made upon a
gypsum base will prove much more satisfactory for the
painter's purposes than the others. Gypsum seems to
have the property of holding up the color and keeping
it from fading, or rather of keeping it from darkening, as
is natural for the crocus or oxide of iron.

It has been seen that Venetian red is an artificial color,
and that therefore it must contain, and in fact does con-
tain, varying quantities of ferric oxide. So one must be
prepared to allow considerable latitude for variations in
this regard. A good sample should not contain less than
20 per cent in its composition. Again, the mere reading
of an analysis would throw but little light on quality, as
some of the poorest of the natural calcined earths which
are sold as American Venetian would show up a very
much higher percentage of it than the best of the gypsum-
base made ones usually do. Some of these cheap cal-
cined earth reds show from 25 to 65 per cent of ferric
oxide in their composition — such as it is. Most of
these are only fit for the mortar heap as colors, and the
difference in cost is so slight that they should never be
used as pigments for painting when the better qualities

110 MODERN PIGMENTS

can be had — even if it were at a much greater difference
in cost than that which really exists.

Venetian reds made upon a gypsum base are reliable,
and practically unchangeable by exposure to light and
air. They darken a trifle, but that is caused chiefly by
the darkening of the linseed oil by age. There is a cause
for this belonging to the pigment itself, and that is the
absorption of a small percentage of hydrogen from the
atmosphere, and of a partial hydration of the oxide con-
verting it into hydrate-ferric oxide. This is very slight
and hardly worth reckoning in the gypsum-based reds.

Venetian red, either the natural or the artificial, may
be mixed with other pigments with perfect safety, and
it is invaluable for mixing with white lead for the com-
pounding of many tints.

It can be used for any kind of painting in oil or dis-
temper. The better grades contain an excellent body
or opacity, and usually will cover solidly over any other
color on which they may be applied in one coat.

It is used as a ground coat somewhat lightened up with
white pigment, for the more expensive reds in coach or
carriage work, for the reds used in painting agricultural
implements and machinery of all kinds. It is one of the
few colors that cannot be spared, and if lost (which it
is not likely to be) could be replaced by no other red
pigments.

INDIAN REDS

Production and Preparation for Use

This most excellent pigment has been known from the
earliest ages under various names, usually derived from
the countries from which it was formerly produced, as
Indian red from India, Persian red from Persia, and so
on. By far the greatest quantity of it that found its

RED PIGMENTS 111

way into England, and from thence was exported to
America, was shipped from Bengal. Hence its name of
Indian red, by which it is best known in both countries.

It is a very rich hematite iron ore. Its coloring matter is
peroxide of iron. It is an anomalous red of a -purple-russet
hue, and highly valued when of good quality for its lakey
tones in making tints by compounding with a white base.

It is a coarse powder in its native state; full of hard
and extremely brittle particles of dark appearance and
sometimes magnetic. It is greatly improved by grinding
and washing. Its chemical composition is such that it
has a tendency to deepen. It is most permanent; neither
light nor impure air, mixing it with other pigments, time
nor fire, seem to cause it to change in any way.

Being very opaque, it covers remarkably well. The
tones of Indian reds vary greatly in their hues; that
which is rosy being considered the best, as affording the
purest-toned tints.

As long as Indian reds were imported and consisted of
iron ores, and until such recent times as the eighties, there
was and could be no recognized standard of purity for it.
Containing great strength of coloring matter, it was the
usual thing to adulterate it with from 50 to 75 per cent of
makeweight foreign matter, and still it remained strong
enough to disarm the suspicions of the painters of that
period. Now, however, it is different. No Indian red
can be recognized as pure that does not show upon analy-
sis at least 95 per cent of peroxide of iron, and frequently
some are found to analyze 97 and 98 per cent pure. The
reason for this great purity is that to-day most of it is
made artificially, as pigments having iron as a coloring
agent are nearly all so made. It is thus possible to main-
tain a specific standard of purity in the processes of their
manufacture.

112 MODERN PIGMENTS

It is made in a similar manner to that related of the
manufacture of crocus used in the production of Venetian
red, with this difference, that instead of sulphate of iron
being the source of supply, iron pyrites replaces it.
The processes vary to some extent from that also ;
these are too complicated for description here, but may
be inferred. The sulphuric acid is driven from the pyrites,
and the residue forms the base of the Indian red.

Properties and Uses

A peculiarity belonging to all iron pigments, and also
common to Venetian red, is that the lighter the tone, the
stronger it will prove in coloring matter; thus the darkest
shades of them are the weakest in this respect. Hence
the rosiest of the Indian reds are the strongest.

Indian reds are selected and graded according to their
shade, and it is usual for color grinders to put them up in
three different shades — the pale, or rose toned ; the medium
or the one between that and the dark which makes the
violet shades. The pale produces the rosy tints, and the
dark the lilac-toned ones. Indian reds are chiefly useful
for the making of a wide range of beautiful tints associated
with a white base. It is also used as a self color, but in a
very limited way.

It is employed by all classes of painters, decorators,
and artists for painting in oil, in japan, or in distemper,
and with universal satisfaction.

TUSCAN RED

Manufacture

Tuscan red is a compound color; properly it is an
enriched Indian red. All that has been said of Indian red,
applies to it in a great degree, as that pigment is the

RED PIGMENTS 113

base. The enrichment is due to the use of a lake to dye
the Indian-red base and give it the beautifully subdued
crimson tones.

As usually the Indian red is entirely too strong, its
strength is reduced by combining it with barytes, whiting,
or gypsum. The combining is done in a tank by the
addition of water with trituration. While still in a
diluted state, the lakes are added to the mixture. The
color is allowed to deposit, when the supernatant water is
withdrawn, the pulp color pressed out, dried and pul-
verized, packaged, and sold as Tuscan red.

Properties and Uses

It stands to reason that the better the lake used in
dyeing the Tuscan red, the better that will be in quality.
If the red has been colored up with the cheaper and
inferior aniline dyes, — as in making the qualities of Tuscan,
— it will fade away upon little provocation, and prove as
fleeting as rose pink and as prompt in disappearance.

Again, in the best grades of Tuscan reds the enriching
lake is practically permanent, or the manufacturers could
never guarantee them to stand 350° F. of heat before
any sign of changes taking place in any way. Tuscan reds
made thus are therefore very permanent, and are ex-
tensively used for the painting of passenger cars, one
of the most rigorous tests for any color; they are also used
with good results in the painting of steam pipes, radiators,
etc., another very hard test of the permanency of a color;
probably Tuscan red is more extensively used for such
painting than any other color. The quality test is the
all-important one for this pigment. The test for mere
strength of the amount of coloring matter contained
amounts to nothing, Tuscan reds being never used for
the making of tints. In this regard they are very inferior

114 MODERN PIGMENTS

to the Indian reds. They are used exclusively for solid
self-painting, and for this purpose are very much better
adapted than are the Indian reds, because they possess
far richer tones.

It is really difficult to test Tuscan reds. The staying
quality of tone is what counts with them, and that is not
easily determined on the spot — time only can do that.
Some of the very poorest ones will show up bright and rich
when first taken out of a can. This is where confidence
in the name of the manufacturers will have to decide
which of two samples one shall buy. If they have an
established reputation made for their Tuscan red, let that
guide. When so found, better be slow in changing to
another that is unknown.

It is used by many manufacturers of machinery and
implements, and when it is properly striped with a light
orange it presents a fine effect. The machinery looks
rich but not gaudy, and it is a relief from the overdone
scarlet that it is customary to use for such painting.

RED OXIDE OF IRON

Properties and Uses

Within the past twenty-five years, the red oxide of iron
has been so listed by many color grinders. It is a power-
ful red and to be had in many shades. The scarlet shade
is the most preferred. These scarlet oxides are the
brightest and strongest known. They should be pure,
and this the scale test will reveal at once. When used
in oil, it should be thinned to the last degree, as it is so
strong that the color will not show at best advantage
unless it is so thinned.

It is chiefly valuable for the making of tints with white
bases where the least quantity of color is wanted to pro-

RED PIGMENTS 115

duce the desired effect. It is so very strong that one
pound of it will turn a ton of white lead to a decided
flesh tint. In other respects, it is of the same character
of red as the Venetian red, and it is questionable if it will
ever be able to take the place of that red even for the
making of tints, because the base (gypsum) in a good
Venetian red acts as a preservative to the white lead, and
in a small measure helps to retard chalking. This is
also partly due to the greater quantity of linseed oil which
a tint so prepared will contain.

Scarlet oxide of iron, notwithstanding that it is abso-
lutely pure, has never become popular among the painters.
It is now nearly twenty-five years since it was first offered
for sale in a regular way, but its growth into favor is so
slow that some grinders who listed it a few years ago
have abandoned it. At best it is a curiosity. Should
it ever grow into favor, it would soon be placed on sale
again, as it is as easily procurable as the crocus of the
Venetian red. The trouble is that it does not fill a
" long-felt want," and that it is only a stronger edition of
Venetian red, and that is of questionable value.

CHAPTER X

RED PIGMENTS (Continued)

RED LEAD

History and Chemistry

THIS pigment was known to the ancients, and is of great
antiquity. It was known and used in the enameling of
pottery, brick, and terra-cotta by the Greeks and Romans,
and was used also by them in their decorative paintings.
It was formerly known under the name of minium, and is
still known under that name in many parts of the world.
It is the product of the oxidation of massicot, but it is
also obtained by the calcination and oxidation of white
lead. It is a double oxide of lead, massicot or litharge
being the monoxide of it. Its chemical formula is Pb4O5.

Properties and Uses

Red lead has the property of saponifying linseed oil to
the extent of about one third of the quantity necessary to
thin it for application with the brush. It is a very good
and strong drier of linseed oil, and for that reason, joined
to that of the saponification of it, it cannot be ground to a
paste form with linseed oil as most other pigments can
be, as it will solidify into a hard mass in a short time.
Owing to this peculiarity, which is a common property of
all the other oxides of lead, it is usual to buy it in a dry,
powdered state.

Red lead is a most excellent paint for use over iron as a
primer next to the bare metal. It is also a most excellent

116

RED PIGMENTS 117

primer for other metals, and it is becoming more important
every year now that so much structural iron and steel are
being used in the construction of buildings in all our
large cities. Engineers and architects are unanimous in
recommending it as a first or priming coat over iron, and
many specify it to be applied at the rolling mills. It is
the best primer that can be used for such a purpose.

Formerly it was extensively used in wagon painting for
the running gears, and some factories still use it in that
way. It seems to adhere with such tenacity on the wheels
that it is not easily scratched or marred. The felloes of
wheels painted with other materials soon show.

Like all lead pigments it is easily affected by sulphur-
eted-hydrogen gases, and it will turn black when exposed
to them. When exposed to the direct action of the sun's
rays it has a tendency to bleach. This is no doubt due
to the loss of some of its oxygen and to a return towards
a monoxide state, the normal condition of the lead oxides.

As to its wearing qualities, there is nothing in the line
of pigments that equals it. It becomes nearly as hard as
a coat of metallic lead itself — some say harder. As has
been said, a wagon's running gear painted with it will
stand knocks, friction, and anything in reason without the
paint coming off, while any other red would come off to the
bare wood.

At the several navy yards of the United States, but
especially at Norfolk, Va., the authorities have come to the
conclusion that there is nothing to equal it for the priming
of iron, and they specify its use for that purpose in ship
construction. Again, when at the end of a cruise ships
come in for a general overhauling in the dry docks, and
after the old paint has been burned off, they are invariably
treated to a coat of red lead as a foundation for whatever
may be wanted to go on top of that.

118 MODERN PIGMENTS

On account of its heavy weight, it is never used in dis-
temper; and from its tendency to blacken under the action
of sulphurous fumes and to lighten under strong sunlight,
it is never used for that kind of work.

Its chief and best use is when associated with linseed
oil for the purposes already indicated.

Many of the white lead corroders also make red lead.
This they put up in wooden kegs of same weights as those
of white lead, viz., 12J's, 25's, 50's, 100's, 200's, and 250's
being the usual quantities. It is usually pure when the
label says "Strictly Pure/' and is accompanied by the
name of the corroding firm. There is some difference in
the qualities of it, some being more crystalline than others,
and therefore richer in tone. It therefore requires some
little knowledge of brands to be able to buy the best
without seeing them first. For the priming of structural
iron, this does not make any material difference; but if
the lead is to be the finishing coat, as in wagon-gear paint-
ing, then that is another story.

The above ends the list of useful red pigments
employed in general painting; the remainder are mainly
compound pigments and the lakes, which are seldom
handled in general painting excepting in tinting or color-
ing walls and for decorative purposes. The car and
carriage painters, however, use some of these extensively.
The japanning works also use them, and some are used
for enameling pottery and colored brick.

LAKES.

General Remarks Concerning Them

Under the generic name of lakes, a class of pigments
is placed upon the market which differs in one respect
from all the others. As a rule they are transparent, and

RED PIGMENTS 119

are never used alone as a covering coat in oil painting.
When used in oil or varnish, it is over some other coat
of color which sometimes is similar in tone to that of
their own, but which has made a solid covering, and they
are used in that case for enriching it. Or if placed over
a color which is dissimilar in tone to their own — one
that will show through their own coating, which permits
certain effects to be thus produced which would not have
been possible otherwise. This is called glazing, in the
parlance of the craft. That is their chief use in oil or
varnish. Some also make beautiful tints with white lead
or zinc white bases, especially the latter, and that with
any of the vehicles.

Lakes are extensively used by the wall-paper manu-
facturers, and in distemper by all classes of decorators
and artists. The car and carriage trades also use them
largely, and artists would hardly know how to get along
without them.

Lakes are invariably made by the use of a dyeing
agent upon a base that it is calculated will best hold it.
For this purpose, many substances and combinations of
them are used. Alum is commonly the principal one,
but gypsum, whiting, and barytes are also employed for
the purpose.

RED LAKES

Among the reds are to be found some of the most valu-
able and permanent of the lakes. This permanency was
originally due to the use made of coloring matter
extracted from the madder plant. This is now obsolete,
as the same coloring substance which was at one
time extracted from the madder root is now much
more economically extracted from coal tar as alizarin
and purpurin.

120 MODERN PIGMENTS

ALIZARIN AND PURPURIN

Extraction and Preparation

Church says: "Both of these coloring substances are
now made from anthracene. This compound occurs in
coal tar in a crystalline fluorescent hydrocarbon C14H10.
By a series of processes this substance gives rise to
alizarin and purpurin, which are in all respects identical
with those coloring matters derived from the madder
plant itself. The artificial alizarin of commerce contains
several other coloring matters, two of which are better
known than the others: these are anthrapurp^irin
(C14H5O8) and purpuroxanthin (C14HgO4). Purpurox-
anthin is also present in the natural pigments derived
from madder root, but it exists in smaller proportions.
Of all these compounds alizarin is the most important
and best known, and yields lakes having various hues of
crimson, rose, purple, violet, and maroon according to its
purity, its concentration, and the nature of its base
(alumina, iron oxide, or lime with alumina) with which
it is associated. The purpurin and anthrapurpurin
resemble each other closely, and give pigments
which are generally characterized by more orange and
red hues than are those obtained by alizarin. The
rose and pink madders and madder carmines of com-
merce are generally so manufactured as to include for
their coloring constituents much alizarin and very
little purpurin."

The process of extracting alizarin and purpurin from
madder root or from anthracene is far too lengthy and
complex for this treatise. It suffices to know that it is
now possible to obtain, at a comparatively low cost,
excellent pigments which twenty-five years ago would
have been very expensive.

RED PIGMENTS 121

Manufacture of Lakes

The preparation and manufacture of lakes from
eosine, anilines, alizarin or purpurin, present no difficul-
ties. Of course, one must be provided with the proper
manipulating devices.

Madder lakes can be readily prepared from alizarin
and purpurin, by dissolving those substances in the
smallest necessary quantity of alkali, such as ammonia
or sodium carbonate, or some pure, freshly precipitated
and thoroughly washed aluminum hydrate. While the
above directions are simple, there is more to that simple
process than appears upon the surface. There are many
little tricks of the trade that are secrets, and which are
used in the precipitation of lakes, which enable one color-
maker to produce from the very same substances a lake
that looks brighter or which is more permanent than
that made by another manufacturer.

Fixing the coloring matter is an important item in the
manufacture of lakes. As an illustration of how trifles
affect coloring matter and its durability, an incident,
the truth of which can be vouched for, is given as follows :
The world-wide known and justly celebrated govern-
ment institution in France — the "Gobelins" — where
the famous historical tapestries are manufactured, pre-
pares all the dyes used in the coloring of the wool. In
earlier days there were no underground sewers in that part
of the city of Paris, and surface streams were depended
upon for the carrying away of all sorts of liquids. It
happened that a small brook formed the middle of the
street in front of the factory, and that the water used for
the preparation of the dyes was taken from it. The
water was very impure and fetid, as it was contaminated
with animal matter from an abattoir (slaughter house)

122 MODERN PIGMENTS

above it. In the course of the city's improvement, the
stream was diverted and made to flow into underground
sewers, so that the Gobelin factory was forced to use city
water in compounding its dye stuffs, but some of the most
admired shades could not be reproduced. It puzzled the
heads of the institution for many years, searching for the
cause of their inability to reproduce the beautiful color-
ings made in former years. At last they hit upon the
cause, and, as nearly as possible, they artificially con-
taminated the pure water furnished by the city to resemble
that which they had once used, and thereupon they were
able to reproduce the shades as of old. These were due
to the impurities contained in the water. This illustrates
why it is that some manufacturers are able to and do put
out brighter and better goods than another can. This is
due in many instances to the water, or rather to the
composition of the water used.

ROSE PINK

Properties and Uses

Rose pink is a very cheap lake of purplish-red tone, and
about the poorest one in the whole range of red lakes.
Its coloring matter is evanescent. It should never be
employed for lasting work.

It is used for coloring fillers in furniture factories, also
by some for staining cheap furniture and chairs. It
looks rich, and usually remains so long enough to enable
the furniture manufacturers to dispose of the goods before
it disappears.

The best of it is usually made from Brazil wood ; some
of the cheapest of the cheap aniline dyes seem to have
gone in the makeup of many samples of it. As there is
danger to those who use this pigment — they may be

RED PIGMENTS 123

using some of the aniline-made ones — unless one is sure
of the brand being a good one, it will be best to let it
alone and take no chances. Much better lakes can be
had which produce the same effects, but they cost more.

ROSE LAKE

Properties and Uses

This lake is just one notch better than rose pink. It
belongs to the same order and tone of red, but, as usually
made, is just a trifle lighter toned and more rosy. It, too,
is made from Brazil wood when it is not made from
something else (aniline).

Like rose pink it fades away quickly upon exposure
to strong light, and but for the fact that one is charged
a little more money for it than for the other, it would be
hard to tell which is the poorer of the two. In reality
it is simply a lighter shade of rose pink, of a more rosy
tone, or not quite so purplish.

The same caution given under the heading of rose
pink — not to make an indiscriminate use of it — will
apply with full force to rose lake. This is also
employed for the same purposes.

MADDER LAKES

Properties and Uses

Under this name will be found all the red lakes found in
commerce that are of any good at all. Accordingly, all will
be listed under the same heading, — all such at least that
are made by the agency of alizarin and purpurin. These
lakes have quite a wide range of tone, and cover the whole
field of maroons, violets, and the pinks, including the
carmine shades.

124 MODERN PIGMENTS

It is useless to examine them separately, as all have the
same general characteristics, the difference being simply
one of tone. Each of them will, of course, make a line
of tints appertaining to its coloring.

All color manufacturers usually put out several lakes
under fancy and proprietary or copyrighted names.
Coach color catalogues and price lists are frequently a
puzzle to the uninitiated because of some dozens of red
lakes of whose existence but few may be aware. Many
are never mentioned by the other competing firms, who
have a puzzling list of their own. Dry color lists are also
swelled up and loaded down with terms to the confusion
of the average reader. Each manufacturer adopts a
name of his own for something that is identically the
same as that chosen by other competitors, each of whom
calls it by a different name. This practice is highly confu-
sing to persons who are not familiar with the trade custom
nor with the exact character of the goods themselves.
Therefore, if a person has been buying a red lake under the
glowing name of "Morning Star," and he finds one that
matches it but offered for sale under the name of " Setting
Sun," he need not worry if he is forced to use the latter.
In all likelihood they are identical, and he will not be
disappointed in their use. The main point is to insist
upon getting an alizarin or purpurin red, and the dealer's
guarantee that such a lake is thus made is the main thing.
Dealers who handle lakes should be able to answer such
questions; and, if they were questioned a few -times, would
be forced to post themselves if they do not already
know — and the y should know — what sort of material
they handle and offer for sale.

The madder reds and madder lakes are, all of them,
what may be called permanent under proper conditions,
and can be called so by contrast and in comparison with

RED PIGMENTS 125

those made from cochineal, Brazil wood, etc. They are
very satisfactory in use. The range of color, covering
as it does every shade of red, purple, and maroon, is
sufficiently varied for the wants of any one. As they
enter into the composition of the better class of vermilion
reds, these might also be classed with them; thus the field
of reds would include the scarlet tones. However, those
reds are solid opaque covering goods, in nowise trans-
parent, and they cannot be included with the lakes.

There are a number of reds made in a manner similar
to the lakes, but upon an opaque base. These are used
for solid painting on that account, and for that reason
these reds cannot be classed with lakes.

The crimson solid-covering reds are chiefly used by
the carriage trade, and are known under various names,
unfortunately all proprietary, thereby causing more con-
fusion. Of this description are the many road-cart reds,
so called. The cheaper kinds of those reds are made
from cheap aniline dyes, and are therefore fugitive; the
better are from alizarin and purpurin, and they conse-
quently are durable.

The scarlet and the carmine-toned lakes are intended
to imitate the true carmine obtained from cochineal.
This they cannot do in reality, for if placed side by side,
the cochineal carmine is the richer by far for a few days.
Change that to a few weeks, and the alizarin carmine will
become the brighter and richer of the two. An expos-
ure of six weeks will do that. v

These lakes (the whole range of them) are useful in
either oil, japan, varnish, or distemper; in distemper,
however, all are less permanent than they are in the other
vehicles, as these protect them.

Certain of the proprietary reds used in coach work are
remarkably well-made goods, and but for the impropriety

126 MODERN PIGMENTS

of giving some of these a free advertisement, and also of
doing sundry others, probably as good, an injustice by
not also naming them — the author does not claim to
have tested them all — therefore he refrains from nam-
ing any. The mention of their existence is sufficient,
because the reader is made aware of their character.

INDIAN LAKE

Properties and Uses

Some few decorators and artists still cling to this lake,
but there are no good reasons why its use should not be
abandoned altogether. It is universally admitted to be
very inferior to the madder lakes, but it is somewhat
more permanent than the cochineal lakes, and that
is probably why some continue its use. The excuse
is a very lame one. It is far less brilliant than and
very much inferior in durability to the madder lakes of
corresponding tone.

Indian lake is a lac of a resinous character produced
by various plants in the East Indies. These are punc-
tured by the larva of the Coccus Lacca, and the result
of the puncture is the resinous lac, from which the
color is derived. It varies in color according to the
plant from whence it is derived. This resin is pounded
in water, the water becomes red, and after having
been boiled down, the residue made by the evaporation
is the crude lac dye. This is dried and made into
cakes. The above suffices to indicate its provenance
and character.

Its use is lessening daily, and it is only a question of
time when it, as well as many other pigments which
have been useful in the past, — for want of better, — will
be known no more, except in history.

RED PIGMENTS 127

CARMINE AND COCHINEAL.

History and Production

Carmine is said to have been discovered by a Florentine
monk, who, while he was engaged in the preparation of
some medicine in which cochineal was introduced,
observed a bright red precipitate. For the sale of this
red, his monastery afterwards became famous.

Carmine is a coloring principle found in the body of a
small insect called cochineal. It is said that the water
used in its manufacture has a great deal to do with the
beauty and brilliancy of the pigment obtained from it.
Otherwise its extraction is a simple affair.

The following will explain in a few words how it is
extracted. Take one pound of powdered cochineal, and
add four or five drams of subcarbonate of soda or
potash. When this has been boiled in soft water for a
quarter of an hour, add eight or ten drams of alum.
After the solution has been effected, take the receptacle
from the fire, draw it off into clean vessels, and after it
has stood for about a week, the carmine will be found
deposited at the bottom. This deposit must be carefully
dried, and then it is ready for use.

There are many other methods of extracting carmine,
but the above is as simple as any, and will suffice.

Properties and Uses

Carmine is a very brilliant color when well made.
Alas! it cannot long resist the action of a strong light,
and it will quickly fade away if so exposed. Its place
is being rapidly taken by the madder lakes, and while it
must be admitted that these are not so brilliant at the
start, in a very few days they appear the more brilliant
of the two.

128 MODERN PIGMENTS

It is very rich as a glazing color over English vermilion,
and is still used for that purpose by the carriage painters,
although even for that purpose many of them have sub-
stituted a madder lake of similar tone, as most individuals
prefer a mediocre stability to a short-lived brilliancy.

It is a pity that such a fine red should be so fugitive,
and for that reason painters who value their reputations
must go slow about its use, and had better let it alone.

There are many other reds that can be found listed in
artists' supply store catalogues, but many of these can be
placed and belong to the reds described, and the rest are
for use in padding the lists; most of them are absolutely
useless even to decorators and artists. Red ochers are
sold under that name and a dozen others. They are
natural reds, the same as the yellow ochers. All such
should be, and in fact are, most advantageously displaced
by the artificially made Venetian reds, as these are uni-
form, and have the color better fixed than the natural
ocher reds, and possess the same range of color tones.
There is no object in retaining the former; they cumber
the red list uselessly. Many are little better than mortar
colors, and are decidedly poor in working qualities.

CHAPTER XI

GREEN PIGMENTS

CHROME GREENS

CHROME GREEN is the one green which is most used by
house painters and decorators, and for this reason it is
given first place here. It has been the aim to notice the
various pigments in a group according to prominence.
It is not possible to do this in every instance. Frequently
it is hard to choose between two which seem to have
equal claims for prominence. In this instance, it is
regrettable that there is no better one to head the list.

Chemistry and Preparation

Chrome green is a compound pigment, not only in the
sense of many other pigments of various substances com-
bined together, but also, in that it is a secondary color;
in other words, that it is of two other distinct colors which
when combined form greens, viz., Prussian blue and
chrome yellow. It can 'be made by a simple mixture
and triturating the pair.

In color works it is never so made. In these estab-
lishments they take the equivalents in chemicals of both
these colors and dissolve into solutions. Then they mix
these together in large vats, and the green is precipitated.
This green is what is known as chrome green in the United
States. By this process, it is claimed that the color thus
produced is more intimately mixed and incorporated.
Besides, it gives every manufacturer room to make the

129

130 MODERN PIGMENTS

claim that by his particular method of handling and pre-
cipitating, he is able to fix the coloring matter much
better than any other maker has ever been able to do,
and also claim superior permanency for the same reason.

Be that as it may, there is one sure thing, and that is,
that certain chrome greens are certainly much more
permanent than others. Some retain their tone much
longer than others, remaining of a decided green after
others of equal strength of coloring matter have badly
faded. A number seem to fade very soon after applica-
tion; others again, like some widows, wait a reasonable
time before changing their dresses.

After the chrome has been precipitated, the supernatant
water is drawn off; the pulp green is put into filtering
cloths and in presses to free it of water. The pressed
cakes are taken to the drying room and left there until
bone dry, after which they are taken out, broken up and
pulverized in the mills, and are then ready for sale as dry
chrome green; or for grinding, in oil, japan, varnish, or
water, for the various purposes for which it is adapted
and wanted.

What has been written above, applies to the manu-
facture of pure chrome greens; but pure chrome greens
are seldom found in the market.

Owing to their great covering properties, and amount
as well as strength of coloring matter, and their great
opacity, there is really no absolute necessity for their
absolute purity. The reason for this is that green is
seldom employed for the making of tints, as are most other
colored pigments. Green is used mostly as color by itself
for the solid painting of blinds for windows, wagon beds,
implements, iron fences, etc. A chrome green contain-
ing only 20 to 25 per cent of actual chrome green, when
it has been properly prepared upon a good base, will

GREEN PIGMENTS 131

cover solidly in one coat any other color over which it is
painted, be it black or white. It would be a waste, there-
fore, to use 100 per cent of color chrome green to do what
20 per cent of it will do as well. The 100 per cent green
might possibly cover a trifle more, as it could be thinned
more; but as no one cares to apply too thin a color, even
that would not amount to anything, and the assertion
can safely be made that one pound of 20 per cent green
will cover as much as one pound of 100 per cent.

Therefore by common consent all color manufacturers
put out a chrome green containing three parts of base to
one part of chrome green. This mixture then contains
25 per cent of absolutely pure chrome green.

The base, of whatever nature it may be or in whatever
proportion it is used, is always added to the chemical
solutions just at the moment of their being thrown into
the vats and before the color is precipitated. The base
and the color are precipitated together. This insures
uniformity.

Nearly all the chrome greens are sold under some pro-
prietary name, such as Crylight, Marseilles, Sylvan,
Emerald, French Imperial, and a host of others entirely
too numerous to mention; but whatever their name may
be, they are all reduced chrome greens and belong to the
class just described. None contain over 25 per cent of
actual color in their composition.

When chrome green is used for the purpose of making
tints with other pigments, either white or colored, the
strictly pure greens should be used, because there they are
the more economical. Such greens can be bought, but
they are in little demand aside from printing-ink manu-
facturers, etc. Many painters make pea greens, olives,
and the various light-toned tints of those and other greens
from ocher chrome yellows, Prussian blues, etc., which

132 MODERN PIGMENTS

they compound without the use of any chrome green.
Hence the pure greens are not always to be found at
paint supply stores, because the demand for them is very
slight.

All manufacturers do not use the same base for the
purpose of reducing the pure chrome green to the com-
mercial basis of 25 per cent, and this of itself accounts for
the difference found in their working qualities. Barytes
is that which is most commonly used for the purpose,
either alone or in conjunction with others. Gypsum
makes the best base for that purpose, as it seems to hold
up the color better, and it also works better under the
brush. Whiting is used extensively also; and added to
either barytes or gypsum to make the paste smoother
in texture, it also helps out in the better brushing out of
the paint.

Properties and Uses

Chrome greens come in two tones; and accordingly as
it approaches to one or the other of these two, the green
is so classed. The two tones are known as the blue greens
and its opposite — the yellow greens. In some of its blue
shades, chrome green approaches somewhat to the tone
of the Paris or emerald green. There is a wide range
to be found in the tones between a very pale yellow green
and a very deep blue green which covers the whole
gamut and chromatic scale of the green tones. Each of
these two groups of green has some uses to which it is
better adapted than the other. As a rule, the yellow-
toned greens are stronger in coloring matter than those
of a corresponding depth in the bluish ones.

One peculiarity that belongs to all chrome greens, but
in a much stronger degree in the blue than in the yellow
ones, is that no matter how carefully they may have

GREEN PIGMENTS 133

been made, if there is any supernatant linseed oil when
a can of chrome yellow is cut open the oil shows up
tinted with blue as if the blue had separated from the
yellow. This property is inherent and does not hurt it.
The necessary trituration of the color before using it will
remedy this condition and reincorporate the trifling
amount of dissolved Prussian blue.

Some of the well-made chrome greens are fairly per-
manent ; but; as any one may well surmise, anything that
would destroy the color of Prussian blue — such as lime
or other caustic substances — will also destroy that color
in the chrome green combination. Sulphureted-hydro-
gen gases which affect chrome yellow, will in the same
manner destroy the color of chrome yellow in the com-
position of the green. So these greens have to carry a
double load of liability to being injuriously acted upon.

Notwithstanding that chrome green is anything but
absolutely permanent, to all intents and purposes it is
sufficiently so, that, for want of a better, it may be fairly
depended upon for many situations and certain condi-
tions.

It is used by all classes of painters, in oil, in japan or
varnish, and in enameling or japanning works. It is
also very useful in distemper work if care is taken in
mixing it that none of its incompatibles be compounded,
or it would then surely fail.

In whatever vehicle it is used, it is contra-indicated
if it is subject to any of the influences which would act
injuriously upon either chrome yellow or Prussian blue —
as under the heading of either of those colors, this is
fully given, and it is unnecessary to repeat it here.

Chrome green and all the proprietary greens — which,
as we have seen, are all chrome greens — come in several
shades. Manufacturers pack it up in cans as: Extra

134 MODERN PIGMENTS

Light, Light, Medium, Dark, or Extra Dark, each of which
makes an entirely distinct set of tints with a white base.

To ascertain the value of a chrome green, it is proper
to make a scale test of it alongside one of the same grade
that is of known standard. With that test one can
readily determine the amount of coloring matter it
contains.

One should never take a strictly pure green to judge
values, and expect one of only 25 per cent of claimed and
acknowledged purity to come up to it. If, however, four
times as much of the commercial grade is taken as is of
the strictly pure, the tints made should be equal.

The reader will find full directions of how to make these
tests at the end of Chapter VI under the heading Chrome
Yellow.

GREEN OXIDE OF CHROMIUM

Properties and Uses

The green oxide of chromium is known to the artists
and decorators of the world under many names, and in
reality is the only green entitled to the name of chrome
green, for it is that. But what we know under that name
in the United States is a different pigment, which, while it
is not entitled to it, is the only one here known by that
name.

Life is too short to start a crusade and to make a
quixotic fight against windmills — which it would be if
the effort were made to change the name — and it is simply
accepted through sheer compulsion; it cannot be helped.

Green oxide of chromium is a good enough name if it is
a bit long in the saying; as it is, it is so seldom used that
it matters but little anyway. Many of the proprietors
of paint supply stores would be puzzled if one was to
call for it, and would not know what was meant.

GREEN PIGMENTS 135

Owing to its limited use, but little need be said of its
manufacture. The intricate processes of manufacture
make it an expensive pigment, and that alone will always
prevent its use, even if it possessed much better qualities
than those which are inherent in it. So that with the
cheap imitation chrome greens, which cover better and
cost ever so much less, there is little danger of it ever
coming into popular use.

Two distinct processes are used in its manufacture,
and these are known as the dry and the wet. Accordingly
as it is made by the wet or the dry process, this pigment
is either transparent or opaque. The latter is the usual
condition under which it is to be found in artists' tube
colors. When made by the wet process the sesquioxide
is thrown down, and that makes it transparent. It is
therefore useful both as a solid color for opaque paint-
ing, or the transparent for glazing purposes. This pig-
ment is somewhat more permanent than the so-called
American chrome green goods which are known and sold
here as chrome green, and it can be mixed with most of
the permanent pigments.

COBALT GREEN (ZINC GREEN)

Properties and Uses

This valuable pigment deserves a more extensive
use than that which it has so far received in the United
States. In Europe, especially in England, France, and
Germany, it is much more popular than it is here. In
America, it is mainly found in tubes for artists' use, and
is seldom ever offered in any other shape. It is imported,
and if manufactured in the United States the author has
never heard of it. There is no reason why it should not
be made here. As I am not familiar with its preparation,

136 MODERN PIGMENTS

I give the following extract from Church's "Chemistry of
Paints":

"It has long been known that the oxide or a salt of
zinc moistened with a solution of cobalt nitrate and then
strongly heated before the blowpipe gives a porous mass of
a beautiful green hue. This compound or mixture of the
oxides of zinc and cobalt may be prepared by: 1st.
Precipitating with an alkaline carbonate a mixture of the
nitrates of cobalt and zinc, and then strongly heating
(after washing) the precipitate formed thereby; 2d,
Making a paste of zinc oxide and water, and adding a
solution of nitrate or sulphate of cobalt or roseo-cobaltic
chloride; the mass is then dried, calcined at a dull red heat,
thrown into water, ground, washed and dried. Method
No. 2 gives a finely colored product, the depth of hue
being proportional to the percentage of cobalt ic oxide.
If the latter oxide amounts to one third that of zinc, the
color is a very deep bluish green; with no more than one
sixth, the color is still rich. Some specimens do not con-
tain more than one twentieth, — occasionally even less
of cobalt oxide, — and yet they are far from pale. An
excellent deep sample contained 12 per cent of cobalt
oxide.

"When properly made, cobalt green is a pigment of
great beauty and power. The deeper tones of cobalt green
are almost transparent in oil. The pigment works well,
is quite permanent, and has no action upon other pig-
ments. Cobalt green is, in fact, one of the two rare pig-
ments which are at once, chemically and artistically
perfect. It must be admitted that it is almost exactly
imitated by a mixture of viridian and artificial ultramarine
with a little zinc white.

"Cobalt green is again coming into artistic use, as it is
equally well adapted for all methods of painting. It

GREEN PIGMENTS 137

was discredited awhile by the inferiority of the product
obtained by Rinmann's original process (No. 1 above)."

It ought not to be an expensive pigment, and if manu-
factured here upon a large scale its cost would be low
enough for use in general painting.

Sometimes the green is prepared by precipitating a
cobalt salt with an alkaline arseniate or phosphate, and
then heating the precipitate with zinc white.

Cobalt green, as was seen above, is more or less trans-
parent according to its depth of tone. The lighter tones
are much more opaque, and these would be the best for
solid painting, but the deep ones used as a glazing coat
over other greens give rich effects. This pigment is good
in any of the usual vehicles, and it is hoped it will become
better known to the general trade. It would be invaluable
to the carriage and car trade; and decorators should use
it more in interiors, where it is free from attacks of the
deadly enemies of most other greens,

VIRIDIAN

Properties and Uses

Again recourse is had to the same source for informa-
tion concerning viridian. Church says of it:

"About eight parts of crystallized boracic acid and
three parts of potassium bichromate are thoroughly
mixed and calcined. The mass so obtained is treated with
cold water and washed by decantation, ground wet,
washed with hot water and carefully dried. The
product is an hydrated chromium sesquioxide in
which a variable amount of the boracic constituent
frequently remains. Viridian, however, is essentially
an hydrated sesquioxide of chromium, having the
formula of Cr2032H2O.

138 MODERN PIGMENTS

"The color of viridian is a very deep bluish green of
great purity and transparency. It furnishes with aureo-
lin on the one hand and with ultramarine upon the other
an immense number of beautiful hues adapted to repre-
sent the colors of vegetation and water.

"It is quite unaffected by sunlight or sulphureted
hydrogen, and it has no eyil action of its own upon other
pigments. Moreover, it can be safely used with all the
painting media and upon all kinds of painting grounds."

It should be more extensively used by the carriage
trade, as it is just the sort of pigment that is needed for
a permanent glaze.

It is chiefly imitated by compounds of chrome yellows
and blues, but such are worthless; they possess neither
the brilliancy nor the permanency of viridian.

Its use is confined to the artist's palette and to the
decorators.

CHAPTER XII

GREEN PIGMENTS (Continued)

TERRE VERTE

History and Production

THERE are to be found in various parts of the world, in
the New as well as in the Old, certain earths having a
variety of greenish tones. These earths vary greatly in
their composition, as one might well suppose, and in
consequence of this are diversified in their respective
colors.

Terre verte was made use of in the earliest attempts
at decoration, and is found upon ancient Roman
wall paintings. The prepared pigment itself has
been discovered in pots in the ruins of the city of
Pompeii.

None of the various shades of this pigment are at all
vivid, and all partake of the tertiary order.

It is prepared for use in much the same manner as was
indicated for ocher and the other earth pigments which
already have been under notice — by washing or levi-
gating to free it from its heavier impurities, and, after-
wards, separating into various grades, then drying,
pulverizing, etc.

The following analysis, made by A. H. Church, is that
of a sample from Monte Baldo in Italy. It shows that
terre verte is allied to the hornblendes, and that it is a
silicious-ferric product :

139

140 MODERN PIGMENTS

Analysis of Terre Verte

Water given off at 100° C. ...... 4.1

Water given off at red heat 4.2

Ferric oxide (Fe2O3) 20.3

Ferrous oxide (Fe20) 2.6

Alumina 1.7

Lime 1.1

Magnesia 5.6

Potash . . . ; 6.4

Soda 2.3

Silica 52.0

From the composition shown by the analysis, a person
can at once infer that terre verte is little subject to change,
as all its constituents are themselves the product of any
and all possible change, and incapable of any further
ones.

Terre verte is only semi-opaque in character, and there-
fore covers indifferently well when mixed with linseed
oil or varnish. Its use in oil is limited to the producing
of certain neutral-toned greenish hues with a white base.
It possesses the quality of absolute permanency, and pro-
longs the life of white lead associated with it in the making
of tints. It does this because of its power of absorbing
large quantities of linseed oil, and acts in many respects
as do all the silicate earths.

It is chiefly used in water or distemper. In distemper
it covers well, and its neutral tones and that of its tints
are much better fitted for mural painting than it is in oil.

Some fine samples of it have been found in various
parts of New England, and many manufacturers grind it
under their proprietary names. Manufacturers of mixed
paints can also use it to good advantage for certain tints
on acbount of its imparting good wearing qualities and
because of its relative cheapness.

GREEN PIGMENTS 141

VERDIGRIS

Chemistry and Preparation

Verdigris is the basic preparation of copper. It is a
permanent bluish green, and is made in large quantities
in Southern France, where the city of Grenoble is head-
quarters for its distribution.

It is produced from copper sheets or plates upon which
the grape pomace, obtained from the wine-presses so
abundant in that section, has been spread. By fermen-
tation, the acetic acid is combined with the copper, and
forms upon the surface a green rust which is verdigris
or the subacetate of copper. It can be manufactured
in various ways, but as the use of that pigment is becom-
ing more restricted every year, and as the description of
the processes would require more space than the little
usage that is made of it warrants, the above, which is the
principal method of obtaining it, will suffice, with this
additional note, that the raw product thus obtained is
afterwards manipulated to free it from impurities. It is
then crystalline, and in that shape it appears upon the
markets of the world.

Verdigris is a perfectly transparent pigment, and its
chief use in decorative work is where that effect counts
heavily.

Its main use to-day is as an ingredient in many anti-
fouling preparations for the painting of ships' hulls
below the water line, especially for the copper sheathing
placed upon the bottoms of wooden vessels. It is claimed
that barnacles and other sea pests which love to attach
themselves to ship-bottoms — thereby causing in the
roughness of their uneven accumulations an impediment
that results in more friction and lessened speed when plow-
ing through the water — that said pests will not attach

142 MODERN PIGMENTS

to vessels whose bottoms have been painted with it.
The poisonous character of that pigment may have some-
thing to do with that; possibly it kills them. At any
rate, their number is greatly lessened when such bottoms
have been painted with verdigris. Sulphureted-
hydrogen gases darken verdigris. It is not safe nor
suitable in any way to use it in water colors, nor is
its use in oil desirable, although when mixed in that
vehicle it is at its best.

It is poisonous, and while not of as violent a character
in that regard as that other copper-base pigment, Paris
green, hereafter described, it is bad enough in that respect
even for use in making a successful suicide. One must
exercise some caution with it.

The use of this pigment has been replaced by that of
other greens, and it is almost exclusively confined to anti-
fouling paint for ship-bottoms.

It is still used as a glazing color by a few old-fashioned
carriage painters.

MALACHITE, OR GREEN VERDITER

Properties and Uses

Under the name of malachite, a natural green
carbonate of copper has been a long time in use as a
pigment. It is mined in various parts of the world,
freed from its impurities, and treated in sundry ways.
Its formula is CuCo3CuH2O2. It resembles in composition
the azurite or blue verditer, but contains less of the
copper carbonate.

It is fairly permanent; but acquires a dull brownish
hue, due to the darkening of the linseed oil; is not
safe as a water color, therefore inadmissible for dis-
temper work.

GREEN PIGMENTS 143

It is so seldom used now, even by artists, that it will
be cut off with the above mention and with a parting
warning for paint students to leave it alone. It possesses
no peculiarity of tone but such as can be obtained by the
use of less dangerous pigments which can be depended
on as having greater permanency.

EMERALD, OR PARIS GREEN

Chemistry, Preparation, and Uses

Paris green is the name under which this pigment is
best known in the United States. It is a beautiful, most
rich and brilliant, transparent green, but for all its beauty,
its violent poisonous properties unfit it for the use of the
house painter, and it is only with the utmost care that it
should be employed by the coach painter as a finishing
glaze. There is, of course, nothing like it for this purpose,
and hence it is that one may be excused in taking some
risk in its application. With a great deal of care and by
the wearing of a sponge at the nostrils during its mixing
and manipulation, the danger is reduced to a minimum.
It affects some painters more injuriously than others.
Some men can never work with it without it making them
sick; such should never use it.

Its use as a glazing color in vehicles is questionable, to
say the least. For a time, while it is protected by good
coats of varnish, it may be safe enough. But when the
varnish decays, and is not promptly replaced, there is al-
ways some danger of particles of it becoming absorbed
into the human system, especially that of children.
They know nothing about the dangerous qualities of the
paint, but, attracted by its beauty, are tempted to rub
their hands over it, and become poisoned. When a
death occurs (and many have happened) from such a

144 MODERN PIGMENTS

cause, what useless regrets it must cause. Therefore the
reluctant advice is given — let it alone.

This pigment is cupric aceto-arsenite, and is permanent
in oil. In water colors it is not, and will not long remain
untarnished in impure air.

SCHEELE'S GREEN

Characteristics

Scheele's green, or cupric arsenite, is another copper pig-
ment. It is an arsenite of copper, and its process of manu-
facture need not be given, as it has become obsolete. In
every respect but one, it is the inferior of Paris green,
and that one is, that, if possible, it is even a stronger
poison. As is the case of many another pigment for which
generations of painters once found some uses, its use to-
day is about nil, and it has been replaced by others bet-
ter adapted to any of the purposes to which it was put
by old-time decorators. Its place at the tail end of green
pigments is well deserved.

Owing to its frequent mention in the antiquated litera-
ture of painters of the eighteenth century, it was thought
best to list it here, simply as a warning example and to
advise against its use.

CHAPTER XIII
BLUE PIGMENTS
ULTRAMARINE BLUE
Chemistry and Manufacture

ULTRAMARINE BLUE is one of the conquests of science of
which chemistry may well be proud. As a pigment, in its
natural state it has long been known. It can be obtained
in its natural state and condition from lapis-lazuli, a
semi-precious stone. There is little danger of the natural
ultramarine ever becoming a dangerous rival of the arti-
ficially prepared ; and if it had to be extracted from the
stone now as formerly, it would hardly be employed as
lavishly as it is to-day.

Chemistry, however, revealed its composition; and ever
since, its artificial reproduction has permitted it to be
furnished at a nominal cost, and put it within the reach
of any one, whereas formerly royalty only could have
afforded its use as profusely as the average whitewasher
could do to-day.

The processes of manufacturing it artificially are well
known, but are very intricate; and until within a com-
paratively short time, this pigment was imported from
Europe. To-day the largest works in the world are
located at Newark, N. J., and produce as good an article
as can be imported from anywhere. All the raw material
that is used in the manufacture of ultramarine is cheap;
it consists of kaolin, or china clay, silica, sodium sulphate,

145

146 MODERN PIGMENTS

sodium carbonate, sulphur, charcoal, and rosin. Calcined
alum is sometimes used instead of kaolin. After heating
the ingredients together in crucibles and then cooling, a
greenish porous cake is found, which is powdered
and roasted (after the addition of sulphur) for several
hours. It requires several powderings, washings, and
dryings, also further calcinations to develop the proper
blue color.

To prepare it for use requires some careful manipula-
tion. It should be washed with water free from lime,
and requires to be finely ground. This improves the
color very much, and any soluble impurities are removed
by these washings.

Properties and Uses

The range of color is great in this pigment. It runs
from a pure blue to a purple blue, and some shades even
border upon the green, and are called green ultramarines.
However, they are not true greens, and they cannot be
listed among them. The shades that are free from purple
are accounted the best, and for the purposes of the painter
are certainly superior, as it is very easy to make a
purple-shaded tint from a blue ultramarine, but it is
impossible to make a clean blue tint from a purple
tone of the same.

Ultramarine should never be mixed with white lead
for the making of tints, on account of the sulphur it con-
tains. When it is used with a white base for that pur-
pose, zinc white is much the best, and the tone of the
tints will be cleaner and purer-looking.

Sulphureted hydrogen does not affect artificial ultra-
marine blue, neither does lime and other alkalies. Weak
acetic acid or a saturated cold solution of alum does affect
it, and in time will destroy it. It may be called a per-

BLUE PIGMENTS 147

manent pigment, as sunlight does not impair it, and it is
useful in either oil, japan, varnish, or distemper; but to
be safe, it should not be used in connection with pigments
that have acetic acid or alum in their composition. It
is always safe when used alone as a solid color or with
zinc white for the making of all blue tints.

The coach painter finds good use for it, both for the
painting of solid surfaces and for the glazing of them
with the transparent kind. As this pigment is usually
prepared, it covers fairly well, but it is inferior to Prussian
blue in this regard.

There is no particular standard whereby to judge of
the value of this pigment other than that it should be of
good blue tone, that it should cover well, and that it
should be strong in coloring matter for the solid varieties;
but the last two items do not apply to the kinds of it
which are made upon a transparent base and which are
intended for glazing.

It is also extensively used for house painting, in the
making of tints with zinc white, as these stand well, and
remain unaffected by sunlight, which cannot be said of
those made with Prussian blue.

For distemper, it is also very useful for wall work and
in decorating.

This pigment may vary a good deal without any
intentional adulteration of it. But, intentional or other-
wise, it should be up to some good sample, which can be
selected and preserved for comparison with it. There-
fore the only rule to judge it by, and the one point upon
which all would agree, is purity of its blue tone and
brilliancy.

It comes to market in its dry state in boxes containing
28 pounds. It also comes ground in oil, japan, or varnish,
as well as in water for distemper painting.

148 MODERN PIGMENTS

PRUSSIAN BLUE

History and Chemistry

This pigment really deserves to be placed first upon
the list of blues. It is probably used the most of
all the blues by painters and decorators, but, owing to its
being more fugitive in sunlight than ultramarine, it was
thought best to give it as second on the list.

Its history now dates back nearly two centuries, and
its discovery was accidental. One Diesbach, in 1714,
while he was precipitating a solution of alum to obtain a
white base for the manufacture of lakes, used some potash
that had been rectified with animal oil, and instead of
precipitating a white substance, it precipitated a blue one.
He had purchased the potash from a man named Dippel,
who, having been informed of the occurrence, traced it to
the proper cause and was able to produce Prussian blue.
The process was kept a secret as long as possible, but in
1724 it was discovered by Woodward, and by him made
public.

Its manufacture is as simple as can be, and is done by
various processes, the necessary agent being prussiate of
potash. This is obtained by fusing the potash of com-
merce with blood or other aninial refuse. After careful
preparation, it is of a yellow color. It is added to another
solution made from two parts of alum and one part of
sulphate of iron, the mixture filtered and allowed to settle.
A double decomposition ensues, in which the iron com-
bines with the potash of the prussiate, forming a sulphate
of potash, while the prussiate of iron is thrown down,
the sulphate of potash being held in solution.

On the other hand, a similar decomposition takes place
with the alum, and the superabundant carbonate of
potash is mixed with the solution of prussiate of potash.

BLUE PIGMENTS 149

By this means a sulphate of potash is formed, and the
alumina or base of the alum is precipitated. These two
precipitates, prussiate of iron and alumina, are produced
at the same instant of time and are intimately mixed,
producing a substance of a brilliant and intense blue,
the Prussian blue of commerce; this, of course, after it has
been well washed and dried.

Whatever may be the system and methods of manipu-
lation,— and these may differ greatly,— the equivalents of
the above must be present to produce Prussian blue.

Properties and Uses

Prussian blue is a transparent pigment of great strength
of coloring matter, capable of absorbing enormous
quantities of linseed oil. On account of the fineness of its
particles, and the still greater fineness which can be given
them by thorough grinding, Prussian blue is held a long
time in suspension before precipitating in that vehicle.

Plow and implement manufacturers use it to paint over
polished steel parts to preserve them from air or moisture,
and consequent rust. In the diluted condition in which
it is used for that purpose, it is thinned out in the pro-
portion of one hundred pounds of linseed oil to one pound
of the pigment.

One may well wonder at the strength and power of
coloring matter. A pound of it will tint a ton (2000
pounds) of white lead to a decided sky blue.

There are two qualities of Prussian blue, which may be
thus described : Quality No. 1 is very good; quality No. 2 is
good for nothing. The good should have a decided blue
tone of great clearness; that is the only tone of it worth
having. The other has a purplish or dirty blue-black
tone, and no amount of trying to doctor it up will help any.
The tints made from it are invariably sickly, miserably

150 MODERN PIGMENTS

muddy-looking, and never give satisfaction. Any tint
made from Prussian blue of good quality and a suitable
white base is very clear, clean-toned, and fairly permanent
under proper conditions. In time it acquires a slightly
greenish hue, but much of this is due, in part at least, to
the change that takes place in the oil. When, however,
it comes in contact with lime, it bleaches entirely away;
even the tints of it made with a white base will suffer.
All the alkalies have the same property, which is fatal to
it. Therefore it is unsuited for distemper work, especially
when the walls are newly plastered, and where it will come
in contact with lime which has lost none of its causticity.

Soluble and Insoluble Varieties

There are two distinct varieties of Prussian blue that
differ only in that one is soluble in water, and the other
is not. In the United States it is customary to designate
as Prussian blue, only the variety which is insoluble in
water; the soluble variety being better known as Chinese
blue or as soluble blue.

CHINESE OR SOLUBLE BLUE

Properties and Uses

Chinese blue is only a variation of Prussian blue. It
possesses all the characteristics of the former with the one
exception, — it is soluble in water instead of insoluble.
On account of its solubility, it is seldom used for distemper
painting. A damp handkerchief laid over it for a minute
will extract color. It is also subject to the same vicissi-
tudes, when it comes in contact with lime and other
caustic substances, as Prussian blue.

After it has dried, when mixed with linseed oil, it is all
right, and moisture will not affect it as long as the linseed

BLUE PIGMENTS 151

oil is undecayed. Therefore for use in oil it is probably as
good as the insoluble or Prussian blue. But, as it is
identically the same thing, there is no need of cumbering
the color list so uselessly as with a separate pigment.
Prussian being the same, and furthermore, insoluble, it is
the better of the two.

As soluble blue, it has uses which are mainly in the
preparation of bluing, either in the liquid form or in a dry
powder for laundry purposes, for the preparation of car-
penters' crayons, and many other economical purposes
which are foreign to the subject matter of this treatise,
and for that reason need not be related here.

CHAPTER XIV

BLUE PIGMENTS (Continued)

COBALT BLUE

Manufacture, Properties, and Uses

UNDER the name of cobalt blue there are several
substances sold which claim to be it. The best known
is that which is made by a combination of cobalt oxide
and alumina. Thenard's blue, another variety of it,
is a cobalt phosphate on an aluminous base.

The first is the less complicated, and can be produced
by calcining a well-triturated mixture of aluminum-
hydrate and cobalt-oxide. The greatest care must be
taken that the material used in the preparation of this
pigment shall be free from iron and nickel; these sub-
stances injure the purity of tone and the brilliancy of
the cobalt blue.

Cobalt blue is a permanent pigment, unaffected by
light, moisture, or by oxygen. Cobalt can be safely used
in true fresco, as it is unaffected by lime. It can also be
safely used with any of the other pigments. It is not
as strong in coloring matter as ultramarine blue, and is
decidedly lighter in tone.

Nineteen twentieths of the cobalt blue that is offered
for sale in the United States, is compounded from a good
quality of ultramarine blue and an admixture of zinc
white, so that its shade may be lightened to that of cobalt

162

BLUE PIGMENTS 153

blue, and of which this makes a good imitation. This
imitation, in fact, is so close that even an expert would
have difficulty in detecting it. To all intents and pur-
poses, when the pigment is mixed with linseed oil, it is
fully as good as true cobalt ; but if used in distemper, it is
subject to the same baneful liabilities which have been
indicated under the heading of that pigment, and
instead of perfect security, which the true pigment would
have given, there are the usual troubles arising from
ultramarine.

It is, therefore, questionable whether it will pay the
painter to buy this as long as there is no assurance
of its purity to be had. It is just as easy to make it
as it is wanted; it is simply an ultramarine tint which
can be prepared by any one from the mixing of ultra-
marine and zinc white.

CERULEUM

Properties and Uses

Ceruleum is little known in the United States. Church,
in his " Chemistry of Paints," has this to say of it:

"When oxide of tin is moistened with a cobalt nitrate
solution and strongly heated, a greenish blue mass is
obtained, which after powdering and washing consti-
tutes one of the varieties of the pigments obtained from
cobalt and known as Ceruleum. There are other ways
of obtaining and preparing this pigment. One of these
consists in precipitating potassium stannate with cobalt
chloride, collecting and washing the precipitate and then
mixing it with some pure silica. Some samples contain
calcium sulphate or lead sulphate in place of the silica;
these are of an inferior quality.

" Ceruleum is a permanent pigment of a rather greenish

154 MODERN PIGMENTS

blue color without any tendency to the violet cast, so
noticeable with other cobalt blues when viewed by gas
or candle light. It suffers little or no change by exposure
to light or impure air, or by commixture with other pig-
ments. It is a sub-opaque, rather earthy pigment with
a moderate tinting power."

Although some painters find it useful, it can really
become so only when used where such deleterious con-
ditions exist as would injure the otherwise excel-
lent imitations that can be made of it from mixing
together in the right proportions, viridian, ultramarine
blue, and zinc white.

It is never offered for sale in America except as an
artist's color in tubes, and is likely to remain so, as the
general trade can readily dispense with it and without
inconvenience.

CHESSYLITE, OR BLUE VERDITER

Production, Properties, and Uses

Chessylite comes from the village of Chessy near the
city of Lyons, France, or rather it is named after it. It
is of the same general character as malachite, and, like
that pigment, is a copper compound, but contains less
hydrate and more of the carbonate of that metal. It
can be produced artificially, but when it is so made it is
not as permanent as the natural.

In the past century, and especially in the first half, it
was much more employed than it is now. The cobalt
blues and their ultramarine imitations have well-nigh
driven it out of the market; and as these blues, to all
intents and purposes, are non-poisonous — while chessy-
lite is not — there can be no good excuse for continuing
its use. It should be abandoned.

BLUE PIGMENTS 155

ROYAL BLUE — BLUE SMALT

Properties and Uses

Under the above name, glass and other vitreous sub-
stances containing cobalt and of a rich blue tone have
long been known.

It is now very seldom, if ever, used, and the term smalt
has itself become diverted from its original meaning, and
is applied to coarsely powdered colored glass and also to
coarsely powdered colored sand which have been artifi-
cially colored not only in blue but in black, or anything
else. This smalt is chiefly used to sand grounds in sign
work, the grounds having first been painted in oil color
of a similar tint to the shade of the smalt thrown over
it — so as to hold the latter.

Formerly blue smalt crystals were finely powdered,
washed, and the lightest-weighted particles were used as
pigment. Owing to its poor covering properties and the
difficulty in using it, it is nearly obsolete, but as it is
indicative of the origin of what is now known as Smalt, it
is well worth notice.

There are several other blues which at times have been
used as pigments either in oil or distemper. All of them
are now obsolete and their place taken by better ones.
The introduction of artificial ultramarine blue and of
Prussian blue has nearly destroyed the trade in other
blues; indigo and other vegetable blues of a similar
character being too fugitive and unstable in strong light,
and all of them are undesirable in many respects.

CHAPTER XV
BROWN PIGMENTS. UMBERS

RAW UMBER
Provenance and Chemistry

RAW UMBER is an earth pigment, and is found in every
part of the world. As may be supposed, it differs greatly
in quality as well as in composition, and its variations may
well be called numberless.

The umbers which have been found and mined so far in
America are very inferior in quality to that which has
come to be regarded as the standard by the color trade.

The umbers mined in England and upon the continent
of Europe come closer to the standard of excellence than
the American umbers do; still, they fall short.

That which is found in the island of Cyprus possesses
in the highest degree all the good points, consequently
it is the recognized standard. Some few samples are
mined in and imported from Asia Minor that are little
short of equaling the Cyprus umbers, and at one time
these were so abundant upon the market that umbers
of good quality were named after them; and even
to-day in the United States all good umbers are sold as
Turkey Umbers.

Umbers are mined like all earth pigments such as ochers,
etc., and in their natural state contain impurities which
are removed by levigations in the manner described under
ochers.

166

BROWN PIGMENTS . 157

The coloring matter of umbers is due to both iron oxides
and to manganese dioxide. To the latter is no doubt due
its excellent drying qualities in oil. The following
analysis by Church shows the composition of a good
sample of Cyprus umber, such as is imported, and is
fairly representative of what the standard of excellence
should be:

Water given off at 100° C 4.8

Water given off at red heat 8.8

Iron oxide (Fe202) 48.5

Manganese oxide 19.0

Lime 1.4

Magnesia 0.5

Phosphoric acid (P205) 2.1

Silica 13.7

Carbonic acid, etc 0.3

100

Properties and Uses

The color of a good raw umber should be a greenish
yellow brown, upon the citrine order when dry. It is
classed among the semi-transparent pigments. It can be
used in oil, japan varnish, or for distemper work, and in
any of the vehicles gives good satisfaction. Without
doubt it is the most useful of the brown pigments to be
found in the whole list. While umber is not so brilliant
as the burnt siennas, it can be used for a much wider
range of purposes, and it is a pure brown. The siennas,
or at least the burnt, should have been classed with the
reds, but the raw sienna is a true brown and this saves
a double classification of it.

All classes of painters regard umber as a necessity:
the house painter to mix tints from it for his drabs and
the various browns; the grainer for most all of his colors
either in oil or in distemper; the coach and car painter
for mixing many popular brown tints; the kalsominer

158 MODERN PIGMENTS

and decorator for making wall tints; the frescoer and
decorators for mixing into tints and for solid work; the
japanner for the hundreds of browns and drabs of which
it is the foundation; and the artists in either oil or water-
colors. What would they do without it?

It is prepared by paint manufacturers in oil, japan
varnish, and in distemper. For the grinding of it in paste
form in oil, it takes up nearly as much linseed oil as do
the siennas. Next to these also, it is one of the hardest
of the earth pigments to grind. When ground in oil it
should be clear-toned without any muddiness, and when
greatly reduced in oil should not show any specks upon
glass. When so thinned out it should be transparent.
Quality gives umbers their chief value; the strength of
coloring matter comes only second to that. The first is
an easy thing to determine by one who is used to handling
them. To test for quality, it should be spread out with
the palette knife and smoothed over the glass. This will
enable one to notice the clearness of tone, its richness and
the fineness of grinding. If one has supplied himself
with a line of good artists' colors in tubes, placing a trifle
of that alongside of the one tested there will be no trouble
in coming to a right conclusion as to the merits of the
umber. It is a hard matter to convey by words, the exact
look a color should have, therefore the advice given
under directions for making color tests — of providing a
full line of good artist colors to judge of the quality
value of pigments — is again strongly urged.

The scale test as previously described, will easily detect
any undue weakness in the amount of coloring matter
contained, and, in a certain measure, the tints made from
them will help in forming an idea of the quality of the
umber. As to the strength of the coloring, one should
not be too quick in condemning the weaker simply

BROWN PIGMENTS 159

because it may not be as strong as another. Between
two umbers, equal in other respects, the better of the
two is the stronger; but between two samples — one
of which is greatly superior to the other in quality —
the poorer may possibly be the stronger. In such a case,
no mere strength can atone for lack of quality. Usu-
ally, however, the better the quality the stronger they
are, so that one need not fear the making of a test for
strength, as it is almost a sure thing that the best toned
will be also the strongest.

The better class of manufacturers are now putting out
their pure umbers under their names and also those of
dependable quality in their best grade. The others under
their names, also put out a pure umber, but sometimes it
is not of the best quality, and in reality inferior to a good
one that is adulterated. At the risk of becoming tedious
in repeating it, the caution is again given: Purity without
quality amounts to little in an umber.

Umbers are not affected injuriously by sunlight, impure
air, nor ordinary heat. By constant exposure to very
high temperatures, it becomes more reddish.

The raw umbers make permanent tints of great beauty
with either white lead or zinc white, chiefly of the drab
order. It is used also in the compounding of a wide
range of tints with other colored pigments, and for the
making of certain neutral greens it is indispensable to
artists and decorators.

.' • : %

BURNT UMBER

Properties and Uses

It is needless to repeat here what has been said under
the heading of raw umber, as very much, in fact nearly
the whole of it, applies with equal force to the burnt.

160 MODERN PIGMENTS

Aside from its tone, which is changed to a deep, rich
brown, all the rest applies to it.

As the name indicates, burnt umber is a calcined umber.
This calcination gives its rich brown color; and in the
better grades, it will be of a clear and pure tone of brown
and entirely free from redness. This is indeed remarkable,
and must be a peculiar property of the iron oxide con-
tained in the best grades of umber, for such a quantity
of iron oxide as was shown in the above analysis of raw
umber ought to make it of a decided red brown after
calcination, and the poorer sorts do show it. So far no
satisfactory explanations have been given which account
for this peculiarity. In the American and other inferior
kinds of umber, the reddish tone shows up, and that is a
"dead give-away" as to their provenance and quality;
so to correct it, these cheap umbers are compounded and
manipulated with a view of correcting this defect. They
are mixed with some of the semi-transparent black earths
to improve the tone and hide the reddishness of it as far
as possible. While the compounding kills to some degree
the redness of the umber, it does not entirely do so, and
the addition of the black earths renders the tone muddy,
and there is no clearness in them. The eye in most
instances is sufficient to detect the imposition.

Burnt umber is used for all kinds of painting, and for
the same purposes enumerated under the heading of raw
umber. It makes a different order of tints of drabs and
browns with the white bases, and can be associated with
any of the other permanent pigments for the production
of an innumerable variety of tints. Some painters have
complained of the tints made from it with white lead
as not being permanent. All pigments which contain
oxide of iron in its natural state, usually have it in an
hydrate form, and after calcination and constant exposure

BROWN PIGMENTS 161

there seems to be a slight return toward the natural
condition previous to calcination; but this in a good
umber is so very slight, that it would hardly be
noticeable. The probability is that in the case of
many of these complaints, the trouble was in the
sinking of the oil and the apparent bleaching out of
the lead. If linseed oil is applied over the faded
part, the color will be restored to its original tint
without loss of intensity. If the color is at fault, the
applying of the oil will not restore the color, if that is
gone. If one has such a trouble, it will be an easy
matter to test it, and to ascertain by the above simple
test where the fault lies.

There is such a thing as false economy; and that it
certainly is, to buy an inferior quality of burnt umber.
Much of the disappointment of painters in its use, arises
from the employment of poor or doctored umbers.

SIENNAS

General Characteristics and History

Siennas — earths, for earth they are — are really a
species of ochers and they do not differ greatly from
them in their chief constituents. It has already been
explained that many of the American ochers border
upon the threshold of the siennas, and on this
account it is sometimes very difficult to place them
properly. The more transparent of them are usually
sold as siennas.

Siennas, then, may be said to be transparent ocher of a
brownish yellow tone. The finest qualities come from
Italy, and, as their name, Terra di Sienna, indicates, are
mined near the city of Sienna. But it is found else-
where and of even better quality. The headquarters for

162 MODERN PIGMENTS

the distribution of the siennas in Italy is the city of
Leghorn, and excellent beds of it are found in the
immediate vicinity.

Chemistry

Siennas usually contain a larger percentage of ferric-
oxide hydrate than do most of the European ochers
proper, as the following analysis by C. H. Hurst indicates :

Hygroscopic water . . . . . 8 . 2 to 17 . 5

Combined water •. . . . . .' 9.0 to 12. 4

Manganese dioxide . . . . . . 0 . 6 to 1.5

Iron oxide (Fe2O3) 45.8 to 59.7

Silica 5.0 to 17.4

The above analysis covers the extremes, and varia-
tions will be found between the two.

Siennas are mined as other ochers are, and they have
to be purified in the same way and manner as was fully
indicated under that heading.

Properties and Uses

It is an easy matter to judge of the value of a
sienna. If the sample to be examined is ground in
oil, it should be spread upon a clean piece of glass in
the same manner as for the umbers. After smoothing
it over with the palette knife, one can judge of its
clearness of tone and transparency by holding it
between the eye and the light. Spreading with a
surplus of oil will indicate the fineness of the grinding.
If it has been properly ground it will be entirely free
from specks or cloudiness, and it should appear com-
pletely absorbed by the oil. In the raw sienna, the
tone should be a clear, subdued yellow, with just the
slightest tinge of brown showing in it.

BROWN PIGMENTS 163

RAW SIENNA

Properties and Uses

Raw sienna is useful for a wide range of work, covering
all the various branches of painting.

To the graining trade especially it is most indispensable;
it could not be replaced with anything else.

The general house painter and the decorators depend
upon it for the making of many beautiful cream tints
in linseed oil, with the usual white bases or with whiting,
etc., for distemper wall work or decorations.

Raw siennas are absolutely permanent. No change
can take place in them when they are used alone and
when mixed with other pigments; the only changes are
such as take place in the pigments with which they are
mixed and which are inherent to them, and, of course, such
changes as are natural to the vehicles used in their appli-
cation.

BURNT SIENNA

Properties and Uses

As the name indicates, this is the raw sienna after it
has been calcined. The roasting or burning produces a
very great change in the color of the raw sienna. It
transforms its color from a yellowish brown to a beautiful
subdued red-brown of great richness. So rich is it,
indeed, in some of the better samples, as to create the
impression in the beholder's mind that possibly it might
have been tampered with, and had been "fixed up" and
enriched by the addition of a lake. Yet in all the best
and finest qualities of that pigment, this richness is
inherent in the sienna itself and this tone is
permanent, which it would not be were it put there by
laking it up.

164 MODERN PIGMENTS

It is the practice of some color makers to use two differ-
ent kinds of burnt siennas in their grindings. They
choose among the samples of native siennas such as are
very strong in coloring matter, and these they grind for
the general trade, who use siennas mainly in the making
of tints with white lead or white zinc in oil or with whit-
ing in distemper. A word must be put in here regarding
the making of tints with burnt siennas. Even the very
best of them do not give as good satisfaction as might
be expected from such fine pigments. The range of tints
made from burnt sienna and the white bases are at best
but indifferent, and as good or better can be made from
the use of Venetian red ocher with the faint addition
of black, at a less cost for material and with equally as
good results as far as durability goes. The grinders, being
aware of this peculiarity, therefore, use an indifferently-
toned burnt sienna which is strong in coloring matter
but deficient in richness; and as this richness is only
apparent when the burnt sienna is used as a self color, it
does not matter. This is sometimes labeled as House
Painters' Burnt Sienna to distinguish it from the other
grinding which they make of the rich transparent kind,
and which is labeled by them as Grainers' Burnt Sienna.
This is intended for use as a self color, and, as such, all the
richness is appreciated fully, and by none more than the
grainers and decorators; this is selected for the very
purpose for which the grainers need them, transparency,
richness and clearness, associated with impalpably fine
grinding. These are not strong as a rule, and, in testing
a sienna for values, the mere strength should never be
taken into consideration in estimating the higher grades.

Volumes might be written, but all would not be said
about the uses and abuses of the siennas. They have
many friends among all classes of painters and artists,

BROWN PIGMENTS 165

and the few who have any trouble with them will find
that they themselves are to be blamed for having used
them for purposes and under circumstances where they
should not have been employed.

VAN DYKE BROWN

Provenance and Preparation

Van Dyke brown is a pigment of bituminous character,
and is usually found in or near bogs. Many theories have
been advanced as to what it really is. Some suppose it
to be a form of lignite, resulting from the decomposition
of vegetation. However that may be, it contains more
or less bitumen. It is found in England and Ireland,
but the best that is upon the market is that which is
imported from Cassel, in Germany.

Vandyke brown is known as cassel earth in many parts
of the world. It contains iron, and should be calcined
and well cleaned of its impurities before grinding.

Properties and Uses

Vandyke brown is used by grainers in both oil and in
distemper, and by some in the coloring of fillers for fur-
niture factories. It is not a permanent pigment, and
becomes lighter and redder by exposure to sunlight. It
is a very powerful anti-drier in linseed oil. It therefore
requires the greatest of care in use. In tone it has a
peculiarly pleasing walnut brown, different from that of
any other pigment. It is very transparent, and that
would make it an ideal grainer's pigment.

But, on account of its defects, it is being gradually
replaced by burnt umber, tinged to imitate its tone and
to correspond so nearly to it as to deceive the casual
observer.

166 MODERN PIGMENTS

It is hardly necessary to observe that tints made from
it with the whites are subject to fade from the same
causes which affect the color when it is used by itself,
and as all the tints which can be made from it are readily
reproduced by using burnt umber, black and blue, and
that when they are so made they are permanent, the use
of Vandyke brown for the making of tints has nearly
become obsolete, and is hardly ever resorted to except
by novices.

The grainers will hardly be willing to part with it for
distemper work in the graining of walnut. It is better
suited to that than any other, as on account of its trans-
parency there is a depth of tone shown under varnish,
which is unattainable by the use of any brown pigment.

METALLIC BROWNS

Preparation and Manufacture

Under that generic appellation, some excellent pig-
ments are produced in the United States. All are native
iron ores or highly ferruginous earths mined in all parts
of the country, but especially in the Appalachian system
of mountains of the eastern seaboard, extending from
Pennsylvania in the north to Alabama in the south.
The Rocky Mountain system contains also some fine
samples of these, and here and there are found outcrops
of them in the great valley between the two. This ore
or iron earth is calcined by roasting, pulverized, levigated,
dried and barreled, and is then ready for market. There
is a great deal of variation in its character and in the
amount of ferric-oxide coloring matter it contains.

The samples vary in the percentage of color contained
to a greater degree than any of the earth colors, ranging
from nearly nothing to 90 per cent of iron oxide. The

BROWN PIGMENTS 167

bases upon which the coloring iron oxide rests vary
almost as much as that. Most of these browns contain
so much coloring matter that the color itself is really the
base, and the other matter found with it is of so small
a percentage that its presence is merely to be considered
incidental.

Properties and Uses

The metallic browns mix readily and absorb a fair
quantity of linseed oil as a rule, the nature of the accom-
panying base having something to do with that. They
range in tint from bright red brown to dark purple,
and all sorts of intermediate shades between these
extremes.

Metallic browns are extensively used for roof and barn
painting, the painting of iron bridges, structural iron and
steel, freight cars, etc.; in short, for nearly everything
where a good substantial covering is required, where the
main consideration is good service, but does not lie in
the beauty of the finish.

They are also useful in the making of certain brown
tints, either alone or as adjuncts to other pigments.
The manufacturers of mixed paints use tons in their
better grades either as bases for the darker tints or as
tinting colors in the making of certain shades.

They are fairly permanent, showing little tendency
to change, other than that pertaining to all iron oxide
pigments — that of darkening by age — but linseed
oil probably is the cause of as much of it as the
pigment. No one should hesitate to use them for
all kinds of work where a cheap, but dependable paint
of no special beauty is required. They can be much
improved in looks by combining with some of the
brighter pigments.

168 MODERN PIGMENTS

They possess great covering properties, and one coat,
even when thinned excessively with linseed oil, will
usually cover solid any other color over which it is
applied.

It commonly comes in the dry state packed in barrels
of 300 pounds capacity. It is ground in oil also, and
put up in the familiar tin packages and wooden kegs and
barrels.

SPANISH BROWN

Properties and Uses

To all intents and purposes, this pigment might have
been included with the mineral browns. As a distinctive
appellation to designate a shade of brown color, it has
no signification whatever to-day, whatever it may have
had in that regard in the past. It is still known and
sold under that name in many localities, but this is
chiefly confined to Pennsylvania, Maryland, and the
eastern and southern seaboard. Since the advent of
the metallic browns, the name has become a memory
with the older painters of the middle and western states,
and is almost unknown to the younger generation of the
craft.

All that can be said for it is that under the name, any-
thing, or rather any kind of a dirty red brown earth, is
usually sold as such, and the grades of metallic browns,
which are sometimes sold as Spanish Brown, are of a
lower order than are those sold under other names.

The use of the name should be discouraged as it is not
best to have confusing elements. The nomenclature of
pigments is complex enough to suit the most fastidious,
and the purpose should be to keep it as simple as possible.

Other substances have been and are listed as brown
pigments by certain houses catering to the artist's trade.

BROWN PIGMENTS 169

None of these have any special virtues worth noticing
here and they are passed by. Most of them are but
variations of some of those that are listed and described —
such as bister and asphaltum — and are so undesirable,
even for artists' use, that they, as well as the painters and
decorators, might profitably learn to dispense with them
as pigments, whatever value they may have in other
respects.

CHAPTER XVI

BLACK PIGMENTS

LAMP BLACK

Chemistry and Manufacture

THERE cannot possibly be any hesitation or uncertainty
experienced in selecting a black for first place on the
list. This place belongs by common consent to lamp
black. Although it is far from being the blackest black,
or the purest toned black, it must be accorded first
place, because of its greater usefulness over any of the
other blacks.

Lamp black is a soot, produced by the incomplete
combustion of resins, resinous woods, fats and fatty oils,
paraffin and paraffin oils. These substances are burned
with an insufficient supply of air, so that a considerable
portion of the carbon they contain may be deposited as
soot. The soot thus produced is far from being pure
carbon, and, of necessity, much of the tarry products of
imperfect production or destructive distillation are present
in combination with it. These foreign admixtures give
it the undesirable tones to be found in the inferior grades.
Owing to their greasiness it is almost impossible to use
them with linseed oil, as they are highly non-drying.
Much of the impurity is deposited in or near the first
receiving chamber, and the lamp black which is deposited
the farthest away from where the substances are burned
is the freest from impurities.

170

BLACK PIGMENTS 171

Calcination in an intense red heat burns up most of
these non-drying oils and tarry products and then the
lamp black is perfect. The first that is deposited is
usually sold dry in the well-known small paper cones,
and these bear no manufacturers' names. The rest is
selected and graded according to its color and freedom
of foreign matter. Usually there are three qualities
selected besides the inferior one mentioned.

Some substances produce a better lamp black than
others, and there are many little tricks of trade and
manipulations known to and employed by certain manu-
facturers that are probably not known to others, as some
do produce much better blacks from the same material.

Properties and Uses

Lamp black being nearly pure carbon is inalterable
and is absolutely permanent and unchangeable.

The oft-cited signboard left and forgotten for genera-
tions in the back yard, and which has had its ground
coats of white paint eaten away, and where the board
itself is disappearing in the shape of lint picked up by
birds, for the making of their nests, until the black letter-
ing painted upon it originally, stands out as if carved
out from the wood, in bold relief among the general
decadence surrounding it, is a very good illustration of
its permanency and preserving powers. Such old-time
signboards may be found and noticed in any neighbor-
hood.

Lamp black seems to act as a preservative from decay
to the linseed oil and to help it postpone indefinitely the
day when it should go the way of all flesh and perish.

One of the chief uses of lamp black is in the making
of gray tints with white lead and zinc white, as the tints
so made are free from the brown gray tones so objection-

172 MODERN PIGMENTS

able in some of the bone blacks, and especially of the red
brown grays produced by the use of gas or carbon blacks.
The lamp blacks give a clear-toned clean bluish gray, or
rather the cast of it, as it is not a blue tone at all. These
grays are distinctively its property, and through them
may be distinguished its purity and quality. Lamp
black is very strong in coloring matter, and its strength
makes it an economical tinting agent.

For solid painting, where an intense black is required,
it may not be as good as some of the bone blacks, but
when any solid black painting is done, where intensity of
tone is not of the first importance, its use will prove much
the most satisfactory.

On account of the lightness of its weight and conse-
quent bulkiness, it is very difficult to mix it with water.
It floats, and no amount of ducking it under will make
it stay down. When it is wanted for use in distemper,
it should first be mixed to a stiff paste with vinegar, in
which liquid it is not so refractory as it is in water. It
can afterwards be thinned with glue water and used for
the making of tints or by itself as desired.

From its great bulk it may be well surmised that it
absorbs great quantities of linseed oil, and it surely does.
In fact, it absorbs more than any of the other pigments.
Owing to the great quantity of oil it absorbs, many
grinders cannot resist the temptation to add some
barytes to it. This can be done without the use of any
additional oil, but this can be detected readily by the
smaller-sized packages required to pack any given weight
of it. The smarter ones put some bulky stuff along with
it, and then the eye will not suffice, and a scale test will
be required to determine its purity. There should be
but very little difference between two samples of equal
purity, as to their strength. However, one may have

BLACK PIGMENTS 173

been ground with more oil than another, or have lain
upon the shelves until the oil has risen; therefore the
samples should be placed upon a piece of blotting paper
and the oil extracted from them so all may be used in
the same form of a very stiff paste before weighing them.
A good lamp black, even the very best, is never of a jet
tone, and alongside of a good bone black it looks grayish
black. Therefore, if it looks blacker than it should to
a person in the habit of using lamp black, it is possible
and nearly certain that it has been bolstered up with an
admixture of gas black.

It is, or rather has been, the habit of some grinders
of small reputation as to the class of colors they put out,
to use a cheap or poor lamp black and to color it up with
carbon black, so that it will pass muster. If this is sus-
pected, it can be quickly determined by simply using a
little with some white lead which should make a gray tint
of it. If it produces the usual gray without any brownish
hue to it, the lamp black is all right; if, however, the tint
so made does show a brownish tone, a solemn oath can
be taken, without fear of perjuring one's self, that
the black has been tampered with and that the tam-
pering agent is gas or carbon black. Any court would
clear one of perjury after reading the evidence presented
by a chemical analysis and the sworn statements of
its examination by experts.

GAS OR CARBON BLACK
Properties and Uses

Gas or Carbon black, as it is indifferently called, is
really only a variety of lamp black. It is produced in a
similar manner as that pigment, but with this difference,
that it is made exclusively from the incomplete combus-

174 MODERN PIGMENTS

tion of natural gas. It is therefore the soot produced
by that commodity.

It is readily distinguishable from true lamp black in
that it is by far the blacker looking black of the two, and
that for jettiness, true lamp black alongside of it — is
not in it.

While the tone of this black is very superior to
lamp black, it possesses some very grave defects that
have in a great measure prevented its adoption for
general use. Should these defects ever be satisfactorily
overcome, it then would become the black, for solid
painting at least.

One of its principal faults is that when mixed with
linseed oil, it livers it. In trade parlance, liver ing means
that peculiar action some pigments have of turning the
oil into a jelly-like condition; it thickens to such an
extent that it cannot be used with the brush in painting.

The livering of gas black is prevented to a certain extent
by compounding it with other pigments, and the best use
that is made of carbon black is when it is associated with
other blacks. The sign writer's so-called blacks are
usually compounded from true lamp black and carbon
blacks.

Its one other great fault has been noted already. It
makes very poor grays, and, while a true lamp black can
be improved with it in self color for solid black painting,
yet on account of its poorness for tints it must be con-
sidered as an adulterant, as the innocent purchaser
might want it for the making of tints, and in that case he
is simply swindled. Why not sell each for what it is
and let the painters do their own compounding? In the
case of a sign-writer's black, it is different. Then it is
not passed as a lamp black or any particular black, and
the name itself indicates that it is to be used for solid

BLACK PIGMENTS 175

painting. If one uses it for making tints, he does so at
his own risk, because the label does not convey any idea
of its fitness for it.

Some manufacturers have put out carbon blacks under
various names, but, for probably good reasons, none of
them have become very popular so far; and while they
seem to have stopped the livering of it, this may have
been done at the expense of another quality of the pig-
ment which has been disturbed by the addition of the
preventive. Be that as it may, it certainly is a fine-
looking black, and it is a pity that it does not possess the
other good qualities of lamp black; if it did — that would
not be in it.

Its best use has been upon ship work. Steamships
painted with it look immensely better than when painted
with ordinary lamp black. Nearly all the transatlantic
lines now use it regularly for that purpose.

IVORY BLACK — DROP BLACK — COACH BLACK

Manufacture and Preparation

Ivory black, drop black and coach black form a trinity of
blacks, but in reality are but one and the same black, with
the exception hereafter named. So it is thought best to
bunch them under one head.

The above blacks are all bone black. The bone black
selected for their manufacture should be from the hardest
and jettiest samples.

Bone black would be too common a name for these
blacks, and probably for that reason it has been dubbed
ivory black. It stands to reason that as there is scarcely
enough ivory in existence to supply the demand for ivory
black in the United States alone for a single year, let
alone the demands that exist for it in Europe and all

176 MODERN PIGMENTS

civilized countries, the black that is sold under that
name cannot be it.

Bone black is properly animal charcoal. This is made
upon the same principle as wood charcoal. The bones
are placed in a retort and are calcined in a hot furnace
where atmospheric air is excluded. The better qualities
of bone black are made from selected hard bones such as
animals' teeth, etc. The resulting bone charcoal is pul-
verized before placing upon the market.

The variety of it known as drop black is the same black
made into little cones of the shape and size of a large
chocolate drop — in which form it was more familiar
to old-time painters than to those of the present day.
These little cones resulted from the bone black, which,
after grinding, had been mixed with water (holding a slight
adhesive in solution) into a stiff paste, and the little dabs
of it placed upon trays to dry were the cones or drops
which gave the bone black the name it still carries to-day
— minus the drops. The drops were placed upon a
marble slab and ground with oil with a muller after first
crushing it. That made life a burden, or at least the
painters of that period thought so, for, if they had a large
job upon which it had to be used, it meant the spending
of their evenings till ten or eleven o'clock grinding away
for dear life.

Ivory and drop black have a small admixture of
Prussian blue added to them to correct any brownish
tone. Coach black has no blue added to its bone black
composition. That is all the difference that there is
between them. A color manufacturer, to whom the
writer had once made the same criticism, laughingly
replied that there was still another difference which had
been forgotten, and when asked what this was replied,
" 'The different labels upon the cans."

BLACK PIGMENTS 177

The ivory blacks are used in oil, japan, varnish and
water. They are good blacks when well made and are
used in all mediums. As an oil color they are usually
too transparent to use for solid painting, except as a last
coat over a previous solid one of lamp black, where that
color is insufficiently black to suit. They are excellent
in distemper, and the grainers find them advantageous
for their work in either distemper or oil, for the
working in of dark veins, knots or shades, for which
they are admirably adapted on account of their trans-
parency.

In japan they are invaluable to the car and carriage
painters. The carriage manufacturers use enormous
quantities of it in the painting of buggies, surreys, coaches,
etc., not only for the solid black painting, but for the
mixing of the numberless dark greens used by the trade
in the painting of everything that runs on wheels.

Formerly every carriage shop used to buy the various
colors ground separately and mix the various shades in the
shop as wanted, but now few of them do so, and these
various dark greens under an array of magnificent names
are compounded and made to match at color works where
the proper facilities exist for handling them to the best
advantage and with the most assurance of duplicating
them semper idem. The multitude of names given
special blacks, or rather grindings of them, is bewildering,
as every manufacturer has a long list of his own which
he tries to make as puzzling as he can, and besides
that he has a number of special-formula blacks which he
grinds for certain carriage factories, each having a special
name. One may as well look for a needle in a haystack as
to try to understand the average coach color list. About
the only indication of quality is the net price, and fre-
quently even that — is not.

178 MODERN PIGMENTS

All this confusion about an article which, when let
alone, is purely bone black, looks to the disinterested
spectator as if there might be some money in it, or it
could not be kept up. If goods were simply labeled and
sold for what they were, as first, second, third, or fourth
quality, or as compounds of this and that, then it would
be easy for one to know what he was buying; while, if the
average buyer can be puzzled, there exists a chance to
demand an undue profit.

The ivory blacks are also used largely by the
japanning plants, enameling works of all kinds, bicycle
factories, etc., they are very permanent under any and
all situations.

CHARCOAL BLACK, OR BLUE BLACK

Preparation, Properties', and Uses

As the name of this pigment indicates, or at least one of
the two names under which it is known in the United
States does give an inkling of its origin. Charcoal black
is a product due to combustion, and, like ivory black, it is
also a charcoal, but there is no bone or any sort of
animal matter in its composition. It is a wood charcoal
and of vegetable origin.

The wood used in the making of it has a great deal to do
with its quality. This wood should be entirely free from
resinous matter. Some of the best of it is produced by the
calcination in a close vessel at a high heat of peach and
plum pits, cocoanut shells, cork waste, grape-vine cuttings,
etc., the powdered charcoal of which forms the blue black
of commerce.

It is, of course, essential in a good black that the cal-
cination should be thoroughly done, so that the product
may be free from any tarry or empyreumatic substances.

BLACK PIGMENTS 179

Blue black is unchangeable and entirely reliable in dis-
temper work, and for that purpose is the black par ex-
cellence. Decorators arid artists use it mostly, and that
only in water colors. It is also used occasionally by some
grainers.

In oil it has little if any body, and for that reason is
seldom, if ever, used but as a glazing color, or for shading,
and obtaining certain effects of depth unattainable with
body pigments.

GRAPHITE, BLACK LEAD, OR PLUMBAGO

Production and Preparation

Graphite is the name under which this substance is best
known as a pigment in the United States, and is a mineral
carbon of a peculiar atomic formation. It is found in all
parts of the known world with considerable difference in
its quality, sometimes varying a good deal in the same
ledge or vein.

That found in the Ural Mountains in Russia is the best
of any mined in the Old World. Mexico produces the
best that has been found so far in the New World. There
is much of it mined in the United States, especially in
New England, and it exists in New York State in the Lake
Champlain region. It is seldom found in a state of entire
purity, and calcination is the means usually employed to
free it from impurities. The ashes of these are removed
by levigation. After repeated washings, it should be
digested with a strong solution of hydrochloric acid to
remove any iron or alumina. After another levigating
it is washed in a leaden vessel with hydrofluoric acid to
remove the silica. After another thorough washing
and grinding to reduce it to a fine powder, it is ready
for use.

180 MODERN PIGMENTS

For distemper work it can be relied upon never to
change. It is also permanent in oil, and when ground in
that media it is of a dark slate color. It is an excellent iron
paint, and is now extensively used for that purpose and as
a paint for tin roofs. The dullness of its color is against
it for anything but utilitarian purposes.

One great fault with it is that it shows markings readily,
and a surface painted with it soon resembles a huge slate
upon which everything that touches it with a little force,
leaves its mark; unfortunately, unlike a slate, it cannot
be sponged off.

There are a number of other black and semi-black
pigments that might be added to the above list, but they
are mostly obsolete, or of such a nature that they do not
deserve notice. For instance, certain black or semi-
black natural earths sometimes listed in catalogues as
Mineral Blacks have never had any standing, nor have
they ever received the recognition of the paint trade.
They have mainly served the purpose of swelling the
lists of a few paint grinders who may possibly have local
trade in them for special purposes to which they may be
adapted or used through ignorance of better.

Such blacks as India ink, which are principally special
preparations of lamp black, do not come within the scope
of this treatise.

The above comprises all the useful pigments. There
are many compounds that are palmed off upon the public
as pigments which will be vainly looked for here. Such
have no more legitimate right to the name than would
have any others of the thousands of tints made by the
combination of true pigments. For instance, the stuff
sold under the name of Gray Ocher, is not an ocher at all,
and is a poor compound of shale or soft, crushed stone.

CHAPTER XVII
A TABLE OF SYNONYMS

No little confusion exists in the minds of many men,
as to what is the right or proper name for certain pigments.
When they happen to know a pigment by a given name,
and it happens that this pigment is offered them by a
dealer or is listed in a catalogue under another title, they
are deterred from using it, as they cannot recognize it
under its other name, and they suppose it to be entirely
different from the one they want.

It is deplorable that there is no universally acknowl-
edged nomenclature for pigments that would be recog-
nized in all languages all over the world, or even an
acknowledged nomenclature for the English speaking
nations.

Custom in the United States is beginning to fix definite
meanings to certain designations, whereby a few of the
pigments and their different, qualities may be known, but
the work is far from complete and from being universally
acknowledged even by our nation alone. So in Canada,
Australia, New Zealand, the British Isles, where trade
connections are not very close with us, the variations
are bound to be greater than the ones which exist here
where the usages of the paint trade have established a
quasi-uniformity in a few of the leading pigments at
least.

The names which have been adopted in this treatise
and which have been given to the various pigments, are

181

182 MODERN PIGMENTS

those under which they are principally known and sold
in the United States.

In the following tables the name adopted as standard
in the preceding chapters for each pigment will be given
preference. It will be placed in the left column. The
synonyms under which the pigment is also known will be
found in the column upon the right, and all bracketed
together when more than one is used.

Thus any one seeking information concerning a pig-
ment which he knows under another name than that
which is given it in the treatise, can readily find it by
looking for it in the right column of the group of colors
to which it belongs, then, having found it, look at the left
column, where he will find the name adopted for that
same color, under which name he will find the des-
cription he seeks.

To facilitate the finding of the names, the same classi-
fication and grouping have been followed as in the descrip-
tion given the pigments. This renders the finding of any
certain color's names an easy task.

TABLE OF SYNONYMS

The White Pigments

White lead

Flake white.
Cremnitz white.
Silver white, or

Blanc d'argent.
Cerusa or ceruse.
Cremser weiss (Ger.).
Blanc de plomb (Fr.).
f Chinese white.

Zinc white

Blanc de zinc (Fr.).

{Carbonate of lime.
Spanish white.
Paris white.

TABLE OF SYNONYMS

183

Kaolin . . .
Gypsum . .

White silicate

Baryta white

China clay.
Sulphate of lime.
Silver white.
Powdered silica.
Barytes.

Sulphate of barium.
Floated barytes.
Heavy spar.
Permanent white.
Permanent weiss (Ger.).
Blanc fixe (Fr.).

The Yellow Pigments

Ocher

Chrome yellow

Baryta lemon yellow

Gamboge
Aureolin

Indian yellow

Yellow ocher.
French ocher.
Roman ocher.
Mineral yellow.
Brown ocher.
American ocher.
Oxford ocher.
Mars yellow.
Mars orange.
Artificial ocher.
Gelben ocher (Ger.).
Mars gelb (Ger.).
Ochre jaune (Fr.).
Jaune de Mars (Fr.).

Chrome.

Chromate of lead.
Canary chrome yellow.
Lemon chrome yellow.
Orange chrome yellow.
Crom gelb (Ger.).
Chrome jaune (Fr.).

Baryta yellow.

Barium chromate.

Yellow ultramarine.

Permanent yellow.

Gomme gutte.
[Cobalt yellow.
{Kobalt gelb (Ger.).
I Jaune de cobalt (Fr.).
rPiuri.

Puree.
jPeori.

Indisch gelb (Ger.)
Uaune Indien (Fr.).

184

MODERN PIGMENTS

Naples yellow

Dutch pink

King's yellow

Cadmium yellow

Giallo di Napoli (It.).
Neapel gelb (Ger.).
Jaune de Naples (Fr.).
Jaune d'antimoine (Fr.).

Yellow lake.
Brown pink.
Citrine lake.
Yellow madder.
Italian pink.
Quercitron lake.
Dunkel gelb lack (Ger.).
Laque brun jaune (Fr.).

Orpiment.
Konigs gelb (Ger.).
Jaune royal (Fr.).

Orient yellow.
Aurora yellow.
Orange cadmium.
Sulphide of cadmium.
Cadmium gelb (Ger.).
Jaune de cadmium (Fr.).
Jaune brilliant (Fr.).

The Red Pigments

Vermilion

Vermilions Reds or Imitation
Vermilions ,

American vermilion

Venetian red

Indian red

Cinnabar.
English vermilion.
Chinese vermilion.
Zunsober (Ger.).
Vermilion (Fr.).

Sold under a multitude of pro-
prietary names.
Chromate of lead.

Rouge.

Crocus.

Colcothar.

Caput mortuum vitrioli.

Burnt ocher.

Sinoper (Ger.).

Rouge de Venise (Fr.),

Ochre rouge (Fr.).

Persian red.
Indian red ocher.
Indische roth (Ger.).
Rouge d'Inde (Fr.).

TABLE OF SYNONYMS

185

Madder lakes

Indian lake

Carmine

Red ocher

Red lead

Pink madder lake.
Rose madder lake.
Madder carmine.
Madder red.
Rubens madder.
Madder purple.
Madder lake.
Madder brown.
Krapp lack (Ger.).
Carmm de Garance (Fr.)
Laque de Garance (Fr.).

Lac lake.

Lack lack (Ger.).

Laque d'Inde (Fr.).

rimson lake.
Purple lake.
Carmin lack (Ger.).
"armin (Fr.)
Laque Cramoisi (Fr.).

Red hematite.
Red iron ore.
Scarlet ocher.
Red chalk.
Ruddle.
Terra rosa.
Miltos.
Rubrica.
Sinopis.
Sinoper.

Ochre roth (Ger.).
Ochre rouge (Fr.).
f Minium
l-Monium rubrum

The Green Pigments

Chrome yellow

Cobalt green

Extra light chrome green.
Light chrome green.
Medium chrome green.
Dark chrome green,

and a host of proprietary names.

Zinc green.
Rinkman's green.
Kobalt grim (Ger.).
Vert de cobalt (Fr.).
Vert de zinc (Fr.).

186

MODERN PIGMENTS

Viridian

Terre verte

Green oxide of chromium .

Malachite

Paris green

Scheele's green

Verdigris

Emerald oxide of chromium.
Mittler's grim (Ger.).
Vert panettier (Fr.).
Vert de Guimet (Fr.).
Vert emeraude (Fr.).

Green earth.
Grim erde (Ger.).
Terre de Verone (Fr.).
Terra verde (Ital.).

{Chromium sesquioxide.
Opaque oxide of chromium.
Grimes chromoxyd (Ger.).
Vert de chrome (Fr.).

Green verditer.

Green bice.

Mountain green.

Green carbonate of copper.

Berg grim (Ger.).

Vert de Montagne (Fr.).

(Emerald green . D ££ K, & f\ {} N/

JCupric aceto arsenite.
(Schweinfurts grim (Ger.).
IVert Paul Verone (Fr.).

Cupric arsenite.
Swedish green.
Mittis green.
Scheele's grim (Ger.).
Vert de Scheele (Fr.).

Basic copper acetate.
Griinspan (Ger.).
Vert de gris (Fr.).
Vert de Montpelliers (Fr.).

The Blue Pigmenti

Ultramarine blue

Chinese blue

New blue.
French blue.
Permanent blue.
Gmelin's blue.
Guimet's blue.
Lapis lazuli blau (Ger.).
Lasurestein blau (Ger.).
Bleu d'azur (Fr.).
Bleu d'outremer (Fr.).

Soluble blue.

TABLE OF SYNONYMS

187

Prussian blue

Cobalt blue

Ceruleurn

Chessylite

Turner's blue.
Antwerp blue.
Berlin blue.
Prussiate of iron.
Chinese blue.
Saxon blue.
Pariser blau (Ger.).
Bleu de Berlin (Fr.).

fKobalt blau (Ger.).
| Bleu de cobalt (Fr.).
[Bleu de Thenard (Fr.).

Coelin.
Cerulian.
Cerulean blue.
Coelin blau (Ger.).
Blue celeste (Fr.).

Blue verditer.

Bice.

Mountain blue.

Azurite.

Berg blau (Ger.).

Cendres bleus (Fr.).

Smalt

Royal blue.

Dumont's blue.

Zaffre.

Srnalte (Ger.).

Bleu de smalte (Fr.).

The Brown Pigments

Raw and burnt umber

Raw and burnt sienna

English umber.
American umber.
Levant umber.
Turkish umber.
Cyprus umber.
Umbraun (Ger.).
Terre d'ombre (Fr.).
Terra ombra (Ital.).

Italian sienna. •
American sienna.
Siena erde (Ger.).
Terre de sienne (Fr.).
Terra di sienna (Ital.).

188 MODERN PIGMENTS

Vandyke brown

Cologne earth.
Cassel earth.
Collen earth.
Cassel erde (Ger.).
Brun de Vandyke (Fr.).

The Black Pigments

T JRuss (Ger.).

Lamp black |Noir ^ fmnee (Fr }>

Drop black.

Coach black, and in japan or

Ivory black J varnish a host of proprietary

names .

Elfenbein schwartz (Ger.).
Noir d'ivoire (Fr.).

Gas black /Carbon black; in oil or japan and

I a host of proprietary names.

[Blue black.

Vine black.
Charcoal black {Frankfort black.

Frankfurter schwartz (Ger.).
^Noir de vigne (Fr.).

Graphite- /Black lead.

(Plumbago.

As many of the artist's tube colors are imported from
Germany and France, such as De La Croix, etc., it was
thought best to give the names of most pigments in the
languages of those countries as the names upon the
labels are in those languages.

CHAPTER XVIII

VEHICLES USED IN MIXING PIGMENTS
THE FIXED OILS

PIGMENTS require various thinning liquids, so that they
can be applied with a brush to the surfaces which they
are to cover over. These liquids must possess binding
qualities so that the pigments may be adhesively
retained upon the surfaces.

Some of the vehicles, as these liquids are called, possess
within themselves the requisite binding properties; others
do not, and must be rendered adhesive by the addition of
other substances which, when mixed intimately with
them, make them artificially adhesive — as water, for
instance, which is the vehicle used for distemper painting.

It is highly proper and even necessary that one should
know something of what is required from the various
vehicles used in painting, and why one is used for certain
purposes in preference to another.

The one which is of the most importance in connection
with outdoor painting, must possess some well-defined
qualifications, as otherwise it would fail to do what is
asked of it. It is an absolute necessity that it should
contain within itself perfect adhesiveness, which will
be referred to as binding quality, and that after it
dries a smooth, waterproof surface may be obtained
that will prevent moisture from penetrating into the

pigment and thus affecting the surface which has been

189

190 MODERN PIGMENTS

painted. The pigments in a powdered condition are
helpless to protect themselves, and none contain adhesive-
ness to hold to the side of a building. It is the vehicle
used in the mixing of the pigment which must be relied
upon to do the binding.

Pigments indirectly affect the durability of the thin-
ning liquids, and a few do so directly.

For outside painting, which is subject to all the inclem-
encies of the weather, — heat, moisture, and frost, — it is
obvious that- the binding vehicle must possess water-
proofing qualities of a high order. It must harden into
a solid mass, for otherwise the paint would be rubbed off
or washed away by rain.

Nearly all oils are waterproof and will shed water;
none mix readily with it; but only a few have the prop-
erty of solidifying into a hard, waterproof mass, and the
oils which possess this power are called fixed oils.

There are many trees and plants whose seeds give
drying or fixed oils, such as the walnuts, hickories, pecans,
flax, poppies, and others.

Flax and poppy are the only plant seeds the paint
world need worry about. These are the two used for paint-
ing, which can be procured at a reasonable price in a
commercial way. The main reason for this is that oils
can be expressed from them much more cheaply than
from any other known plant seeds. Flaxseed is most
abundantly raised as a field crop, and its cost is low
compared to that of any others, not excepting poppy seed.
These two plants possess peculiarities of their own which
make them more desirable than any other for the making
of a paint oil.

Besides possessing the general characteristics which
belong in common to all fixed oils, each of these (linseed
and poppy seed) has its own which make them differ

VEHICLES 191

from each other and from every other of the fixed oils as
well. These peculiarities fit each one of these oils to be
better adapted to a certain purpose than it is to others,
and indicates which of the two it is best to use for certain
conditions. While poppy-seed oil is superior to linseed
oil for some painting (as for zinc white enameling), it is
inferior to linseed oil (as flaxseed oil is universally known
in English-speaking countries). This and the other very
good reason that linseed oil is by far the cheaper of the
two, are the main causes why poppy-seed oil is so seldom
used in general painting. There can be no question as
to which is entitled to head the list of useful vehicles.

LINSEED OIL
Manufacture

Linseed oil is expressed from common cultivated flax-
seed (Linum usitatissimum) . This is grown in all parts
of the civilized world. It grows from almost the sub-
arctic regions down to tropical countries, and even in
these in elevated regions.

The process of extracting the oil from the seed is a
very simple one, and once every little town or hamlet
had its crushing mill and extracting presses. To-day in
this business as well as in that of every other commercial
commodity, the manufacture of linseed oil is in the hands
of large concerns, and the small plants have gone out of
the business.

The flaxseed is ground into meal, and this is either cold
pressed or heated, and the oil pressed out of it by powerful
hydraulic presses. The oil flows out, and the solid parts of
the seed remain in what is well known as linseed-oil cake.

The cold-pressed oil is clearest, palest, and best; but as
by that process it cannot be made to yield nearly so much

192 MODERN PIGMENTS

oil as when the flaxseed meal, has been heated, that is
very seldom practiced now. This is a pity, for cold-
pressed linseed oil is superior for painting purposes, and
is clearer, more fluid, and free from much deleterious
matter which is extracted by the hot system.

There is still another system in use for extracting the
oil from flaxseed, and a still greater percentage of oil is
obtained from it than by the use of either the cold or
hot system of pressing. This is known as the percolation
process.

After the grinding of the flaxseed into meal, this is
placed into a percolating tower running through the
several stories of the factory building. When filled with
flaxseed meal, this is saturated with benzine or naphtha,
and more of that subtle fluid is poured upon the meal at
the top of the tower. This is continued until all traces
of oil have been dissolved and removed from the meal.
The naphtha charged with the dissolved linseed oil runs
downward to the bottom of the tower into a pipe, which
conducts it to an apparatus where it is heated. The
naphtha, being a very volatile oil, is evaporated at a com-
paratively low heat. These vapors are conducted to
condensers, and the vapors soon condense into what they
were originally — naphtha. This is used over and over
again; there is but very little loss of it. The remaining
oil is entirely freed from the naphtha by this heating, if it
is properly managed. It is claimed by some that by
this system, certain substances are dissolved which
would remain undisturbed by pressure, and that the loss
injures the durability of the linseed oil for outdoor work.
This claim, however, may not be well founded, and may
be due to prejudice or the self-interest of concerns that
press oil. Some again claim that it is better. However,
so many from all parts of the country claim differently,

VEHICLES 193

that one should be slow in making the change from one
to the other. Experiment with them side by side under
varied conditions. This system has some good points in
it. Naphtha does not dissolve moisture, and linseed oil
thus made is as nearly free from it as it is possible
for it to be, and this cannot be said of the heat-
expressed oils. The real difference between the pressed
oil obtained by heat and the percolated oil, cannot
be so great as to deter any one from using either, but
the chances are that the old-fashioned cold-pressed oil is
the best.

Linseed oil made by whatever system, may vary a
good deal in its quality from other causes than those
pertaining to the system of extraction. It varies greatly
accordingly as it is made from good or from bad flax-
seed. That made from East Indies, imported flaxseed
(better known as Calcutta seed, from the city from which
it comes) is usually better than that obtained from Ameri-
can seed. Its product, sold as Calcutta-seed oil, is usually
freer from moisture than that which is made from flax-
seed of American or Russian origin. Varnish men who
ought to be good judges of quality in linseed oil, prefer
it to all others, in the preparation of varnishes, as they
must have a dry oil, containing but little moisture.
American flaxseed, when properly harvested, is as good
as any in the world — but there is the trouble, it is not
harvested properly. In America, flaxseed is harvested by
machinery, the same as wheat. Owing to the ease with
which it shells out when the sickle strikes the plant, the
cutting cannot be delayed until the seed is ripe, as it
would all shell out and fall to the ground; so the crop is
cut down before it is ripe, just as the seed begins to change
from the dough state and begins to harden. In that
ccndition, it is saved without shelling — but it is far from

194 MODERN PIGMENTS

being fully ripe. In the East Indies, where labor is very
cheap, it is pulled by hand, when the proper times comes,
and thus they are able to secure it in the very best con-
dition. This is impossible in America, hence American
seed does not equal it.

So with poor seed to start with, and a larger quantity
of oil expressed out of it than in the good old days of
cold presses, there can be no wonder at the complaints
that linseed oil does not wear as well to-day as it did in
old times.

For good work, it would pay to use cold-pressed oil,
even at an expense of several cents more per gallon. It
would pay architects to specify it in their contracts, and
property owners should be willing to foot the slight
increase it would make in their painting bill, if they
could only be made sure that they were getting it after
specifying it and paying for it. But quien sdbe?

Linseed oil, after it has been pressed, should be tanked
for three or four months to allow it to deposit some of
the foreign matter pressed out of the seed with the oil,
and with which it is more or less charged. This will
settle to the bottom of the tanks, and is called linseed-oil
foots. It will do so naturally, if only time enough be given
— but it is not allowed.

Manufacturers being human (in some ways) do not take
kindly to the idea of having vast sums of money tied up
for several months in a tank. They want to turn that
money over and over before the oil would be fit to sell in
the natural way it has of doing this work, so they arti-
ficially hasten this precipitation.

There are two ways of doing this; one is known as the
alkaline process. As this is the poorer of the two, no
time will be wasted upon it. The other is by trituration
with sulphuric acid.

VEHICLES 195

Sulphuric acid does not affect linseed oil injuriously, and
it acts only upon the impurities which precipitate rapidly.
The oil is then well washed with water by trituration
until it is free from traces of acid, and is then considered
fit for use. Varnish manufacturers who are most careful
in the purchase of linseed oil usually still further refine the
oil by repeated agitation of it with sulphuric acid; and the
grinders of fine pigments requiring refined oil, use it also
for the same purpose. With both of these sets of men,
clearness and limpidity are of the first importance; but
painters of the old school who can remember the time
when they went to the town mill and bought cold-pressed
oil settled in the old-fashioned way, and used it to mix
their pigments with, claim that three coats of such oil
and white lead would wear for years before it would com-
mence to chalk. Now a like number of coats prepared in
the old way, but with oil such as it now is, will appear as
so much whitewash in the same number of years. It
will require something else besides plausible talk to make
them believe that the oil they buy to-day is half as good
as the old-fashioned, cold-pressed, naturally settled oil
made from pulled flax which it was possible for them to
buy some seventy years ago.

Chemistry of Linseed Oil

Linseed oil is a complex product, and its drying or
solidifying is due to its becoming oxidized. Condit says:
"To understand the action that occurs when oil dries,
we must know the composition of it. Linseed oil is
composed of linolein, palmittin, and olein. To non-
chemists, these words are mere names; but let us designate
linolein by A, palmittin by B, and olein by C; now A the
first is composed of linoleic acid and glycerine ether,
B of palmitic acid and glycerine ether, and C of oleic acid

196 MODERN PIGMENTS

and glycerine ether. Glycerine ether is the base to
which the other constituents are attached. Looking upon
glycerine as D, we may represent the other constituents
as allotted in this manner:

A —

B

=D

Chemically considered, these salts (A, B, and C) are sus-
ceptible of parting with their base glycerine (D) in favor
of some base possessing a stronger affinity for oily acids."

The Drying of Linseed Oil

"This kind of decomposition in point of fact really
takes place under proper conditions, and the resulting
soap varies in its nature according to the base employed.
Take an instance: Suppose you have rubbed some linseed
oil on a sheet of glass or china (I mention these substances
to preclude the idea of the absorbance of any part of the
oil which would take place if wood, etc., were used) and
it has sufficiently dried not to become sticky, and that
when in that condition you wash it with a solution of soda
in water, the soda dissolves the glycerine to unite with
the oily acids (linoleic, palmitic, and oleic) and forms a
soap, leaving the glycerine free. In other words, using
the above formula: A, B, and C unite with the soda (or
other alkali) and leave D a free agent. Now this D is
soluble in water, consequently the soap which is formed
(by the union of A, B, and C with the alkali) is also dis-
solved. This soap, by the way, is not like the ordinary
hand soap, but is a frothy matter that gathers on the
glass. Hence, by washing the oil with sufficient soda and
water, every trace of oil is carried away from the glass."

The above explains what would take place if the oil
were left in an undried state, and to some extent what does

VEHICLES 197

take place when linseed oil is washed over with alkalies
even when dry. It is the same action which takes place
when the alkaline removers take off paint; but to return
and find out how oil dries, Condit further says:

" In speaking of the drying of linseed oil merely a
change from the liquid to the solid state is meant. Now
the constituents of the four components of linseed oil
consist of oxygen, hydrogen, and carbon in varying pro-
portions; that is, linoleiu A, palmittin B, and olein C are all
made up of the above elements, differing in proportion
just as the letters A, B, and C are made up of straight lines
and curves, differing, however, from each other in the
totality.

"Now in the change from the fluid to the solid con-
dition, i.e., the drying process, oils suffer a slight loss of
carbon and oxygen, but they gain about one tenth of
their own weight in oxygen. It is by this union of oxygen
with the component of linseed oil that they dry or harden.
Put them out of the influence of this element and they
remain fluid. Slow-drying oils lose least in weight; they
contain more of the non-drying fats, and for that reason
seem to gain more in weight (in time)."

The process of drying, while it is very simple, in theory
at least, is most intricate, and would require too many
explanations to follow it up in all its details, so it
cannot be given here as fully as some might wish. To
properly handle the subject would require a large
volume, therefore a resume is given below in short
paragraphs, which contains the gist of the process; it, too,
is from Condit :

" 1. Linseed oil is composed of linolein drying oil, 80
parts; palmittin and olein non-drying oils, 20 parts, of
which 8 parts are glycerine ether which flies away in the
process of drying.

198 MODERN PIGMENTS

"2. Pure oil will not dry in darkness; and the greater
the light, the more vigorous the drying.

"3. Heat is also a powerful drier of oil; oils heated
for a short time continue to dry more rapidly for a long
time after the heating.

"4. Drying appears to be the loss of glycerine ether
and the gain of oxygen from the air, the glycerine appear-
ing to be loosened from the oil acid as the oxygen unites
with the oil, the result of the drying being a light varnish.

"5. Some of the non-drying oil acid also flies away in
the drying, especially under the influence of direct sun-
light or when the oil is heated; 100 parts of oil become
111 parts (more or less) heated; it loses 3 parts (more
or less); net gain 8 parts.

"6. Most of the glycerine ether which is linked with
the oil flies away in the drying.

"7. When oxygen combines with a drying oil — that
is, a fixed oil — caoutchou or gluten is produced, which
in reality is the hard, horny, elastic body that renders it
'dry.' It is the ' skin' that forms on top of a pot of paint
when it has been left undisturbed for some time.

"8. The drying of oils appears to depend upon the
presence of oxygen, which, by an incipient combustion
of hydrogenous oils, fixes them. Whatever contributes
oxygen is a drier, as is the case with pure air, sunshine,
etc. So also the perfect oxides of metals, including even
pure earths and alkalies in due proportion, dry oils; the
best are those which contain oxygen in excess, such as
litharge, sugar of lead, minium or red lead, the oxides of
manganese, sulphate of zinc, white copperas and verdigris."

Properties and Uses

Raw linseed oil is penetrating and elastic, and after its
oxidation or drying it remains as a waterproof rubber-

VEHICLES 199

like substance, holding firmly whatever pigment it has
been mixed with. Some pigments act chemically upon
it, as, for instance, the lead salts, which have the property
of turning it into a soap, which, however, is not a readily
soluble one (after drying at least); the lead oxides are
noted for this property, as red lead and litharge. Not-
withstanding that a great deal has been said as to the
beneficial influence exerted by the totally inert pigments
— which in a measure is true — it is equally true that
some very active ones, combining chemically with lin-
seed oil, exert a very good influence over it, as occurs when
red lead and linseed oil are combined, the resulting
linoleate soap being, when dry, insoluble in water. It
is not acted upon injuriously by that element, which is
most destructive to linseed oil ordinarily. This, how-
ever, is not true of all active pigments, some of them
exerting baneful influences upon linseed oil as they com-
bine with it to form soluble soaps. Pigments containing
lime in a caustic form are of that character.

The inert pigments naturally do not exert any influ-
ence upon it one way or another, and when linseed oil
has been mixed with them no chemical action takes
place; the drying and longevity of the oil remain the
same, generally speaking, as if the pigments had not
been added.

The above statement was purposely qualified by saying
generally speaking, because in one way they do exert an
influence which, while it is not chemical, is a mechanical
one, in this way: Some pigments are very heavy and have
no affinity for oil, and naturally take up but little when
mixing them into a paint; others again are very light
and take up large quantities. It is reasonable to suppose
then that the pigment which has not taken up much oil
will be a drag upon the oil, as a little of it is scattered over

200 MODERN PIGMENTS

a great quantity of pigment atoms, so that but an infin-
itesimal portion has to perform a duty that is above
its strength, and so it is. Such pigments cannot be
depended upon for outdoor work.

On the other hand, the pigment which holds up large
quantities of oil mechanically prolongs its life.

Again, there is a class of pigments containing non-
drying elements in their composition, which prevent the
oil from drying, such, for instance, as uncalcined lamp
black, vandyke brown, etc. These cannot be safely used
without first preparing the oil, so -that it shall contain
sufficient drying energy to overcome their deficiencies.
Artificial driers must be added to the oil to hasten its
drying. Otherwise, these pigments exert a good influ-
ence upon the longevity of the oil, as they take up so
much of it.

Linseed oil continues to absorb oxygen after, seem-
ingly, it is as dry as it is possible for it to be, or long after
it has ceased to feel tacky to the touch. The fact is that
when it has reached that stage where no further oxida-
tion takes place then its downward grade of decay may
be said to have commenced.

Linseed oil, while it may not be as good as it was fifty
years ago, when it was all cold pressed, is usually found
pure, such as it is. It is, of course, possible for some of
the dealers to practice the adulteration of it, but it is
seldom that that occurs. Jobbers, in the past (a few of
them), who did not care for reputation, did mix oils, but
now such a thing is next to impossible. What with
nearly every state having special laws, which no one
would take any risk of infringing, and behind these Uncle
Sam with his own strict laws to prevent fraud — the
practice of adulterating linseed oil has about become
obsolete.

VEHICLES 201

Linseed oils are, however, imitated; but the imitations
are sold as such. There can be no harm come of it, for
no one is cheated. If a painter is foolish enough to
believe all the stuff that smooth-tongued strangers tell
him regarding the merits of nonpareil, indestructible
enamelling liquid, in the way of throwing linseed oil in
the shade, and supplanting it everywhere, he has a perfect
right to believe and to give his money away for it. The
law recognizes him as a free agent and will not forcibly
keep him from flinging cash in the river, if he so wills.
It takes money to buy experience, and with some men
it only seems to last until the next deceiver comes around
with another bait — 10 cents a gallon below the market
on linseed oil!

Barnum said: "For every fool that dies, two are born."
It must be true, or the concerns manufacturing dope oil
could not flourish as they do.

Impurities, and Tests for Them

It is a very hard matter to determine impurities in
linseed oil, and nothing short of an analysis made by an
expert chemist used to that sort of work will be of any
value. This work is intricate and expensive. But
anyone can readily determine to his own satisfaction
whether linseed oil is adulterated or not. At least,
raw linseed oil can be so tested, but not the boiled.
There is no test that one can make for himself that will
do .for that.

There are several tests. One, the most usual, is the
nitric acid test. Although it is a simple one to make, it
is apt to lead many into error, if they are unused to
testing oils. To make the test: Take a bottle, or any
other glass vessel, pour into it about equal parts of raw
oil and nitric acid — one ounce of each is enough for the

202 MODERN PIGMENTS

purpose. Shake the bottle, so as to mix the oil and acid
well together, and put it away to rest for a quarter of an
hour. If the oil is pure, the nitric acid will settle at the
bottom of the bottle, where it forms a distinct layer
below the oil which floats on top. The nitric acid in a
well-made oil will be found clear, but tinged to a light
straw, from coloring matter extracted from the oil during
the shaking; the oil itself in the upper layer will be- found
to have turned to a brownish color, but of a clear tone.
If adulterated, the oil will be from dark brown to black
and muddy, lumpy or "livered," according to the nature
of the adulterant. The acid will be brownish, and often
its limpidity even will be impaired; but not always so,
this depending also upon the nature of the adulterating
oils. It is impossible thus to determine the adulterant
that requires a chemical analysis.

Then there is the specific gravity test, which is always
satisfactory, as it is a very hard matter to adulterate oils
so that this will not be greatly changed. It requires
apparatus to make this test, but that is not very expen-
sive: a suitable hydrometer, one that is adapted to oils
or fats, with a thermometer, are all that will be needed.
The oil should be poured into a vessel, which must be
considerably deeper and wider than the hydrometer,
which is dropped into it, and which must float clear of
the sides and the bottom of the oil receptacle. The
specific gravity of linseed oil is, say, 0.932 at 60° F. Now
if the hydrometer is placed in the oil and the top of the
bulb indicates .928 or .934, if the temperature of the oil is
either above or below 60° F., a correction must be made
for that, as the oil will show a lighter gravity if below the
standard temperature and heavier if above. Deduct or
add .00035 for each degree of variation in temperature
either above or below the standard, and, if the oil is pure,

VEHICLES 203

the total ought to be 0.932. If it varies very much, the
oil is adulterated.

Then there is the flash test, but this is rather com-
plicated and requires more apparatus to determine cor-
rectly. The two above-mentioned tests will be sufficient.
Besides, the nose and the eye can be made nearly as
efficient as any, at least for certain kinds of adulterants.
Linseed oil has a smell all its own, and neutral oils can be
readily detected by their odor with the nose, they have
also a bluish fluorescent tone that the eye can readily
note, so that, with the help of these organs, a double test
can be made, and one or the other will be apt to uncover
the adulteration. The nose will also detect animal or
fish oils, which may be used in adulterating; however, the
chances are that it will be hard to find any as long as they
stay above the cost of linseed oil.

BOILED OIL

As it has already been stated the heating of linseed
oil renders it more drying. When it is boiled at a great
heat along with some of the oxides of lead or manganese
it is rendered thereby still more drying.

For mixing with some of the non-drying pigments,
its use is imperatively demanded, at least for the
grinding of them into pastes. Boiled oil is less
elastic than raw oil, and, being darker, it tinges
the white pigments and some of the light tints to
an undesirable degree. It is also much less elastic
than raw oil and less penetrating, therefore it should
never be used for priming purposes. It partakes of the
nature of a varnish, and dries upon the surface with but
little penetration.

It is therefore better adapted for interior painting than
it is for that of outside work. Its use is indicated, how-

204 MODERN PIGMENTS

ever, for many purposes where penetration and elasticity
are not of prime importance.

Adulteration

Under the heading of raw oil, it was said that all tests
which were indicated for that were useless when applied
to boiled oil, and so they are. It requires an expensive
chemical analysis. Unless, of course, that the adulterat-
ing has been so carelessly done that the nose and eye can
be utilized to ferret it out, as is the case when neutral
oils have been added.

The most frequent adulteration, if adulteration it be,
is in many dealers taking, say, one barrel of raw linseed
oil pouring the contents of it into the boiled oil tank and
adding from five to ten gallons of some cheap benzine
manganese dryer. Boiled oil thus prepared is called
bung hole boiled oil. It is simply raw oil with probably
a bigger dose of liquid drier than would have been the
case if the painter had added it himself.

POPPY SEED OIL

Properties and Uses

As the name implies, this excellent paint oil is produced
from the seed of the poppy plant — opium poppy, or
papaver somniferum. It is nearly colorless and very
clear, so these qualities render it of great value for the
mixing of white pigments or for that of tender
light tints. For China finish or interior enameling,
for instance, it is invaluable. In this connection
it should be used with zinc white in preference to
linseed oil, which has the property of darkening the
more quickly that it is shut away from the sun's
rays. This defect does not belong to poppy seed oil.

VEHICLES 205

Zinc white of good quality is ground in it to a paste
form, and so labeled when offered for sale.

Poppy seed oil is a slow drier, so it requires a longer
time for paint mixed with it to become dry. Its binding
properties are no better than are those of linseed oil —
if as good. Its high cost compared to that of linseed oil
will always prevent its use. It is, therefore, but for
expensive enameling that its use is ever resorted to by
the general painter and decorator. Artists, of course, can
afford to use it, ad libitum, in the very small quantities
they require.

CHAPTER XIX

VEHICLES (Continued)

THE VOLATILE OILS

Spirits of Turpentine

IN defining the word vehicle, it was stated that it was
a liquid medium with which pigments were mixed and
properly thinned, so that they could be spread, by paint-
ing with a brush, over the surfaces to which the painter
wished to apply them; that, through their agency, the
pigments were made steadfast to these surfaces by those
adhering or binding qualities of the vehicles, either pos-
sessed inherently within themselves, or added to them by
the introduction and admixture of binding agents, as
glue or gum arabic, etc., for water; the volatile oils
serve another purpose in painting.

Their binding qualities are little better than water.
This can readily be inferred from the fact that they
evaporate entirely away, so that pigments mixed with
them alone would have about the same chance of remain-
ing upon outside surfaces as they would have if they were
mixed with water instead — till the next hard rain came,
which would wash them away; or some boy, even, without
the rains, could rub the painting off with his bare hand.

The chief use of volatile oils in painting is for the pur-
pose of rectifying some defects in the fixed oils that are
used as binding vehicles in exterior painting, and for
what is called flatting in interior work.

206

VEHICLES 207

As adjuncts to linseed or poppy seed oils, they possess
the property of intimately mixing with them, and of ren-
dering them more fluid (they lessen their viscosity) and
also make the fixed oil set quicker. This enables the
painter to put on a heavier coat of pigment with less
linseed oil than would be possible without the use of the
volatile oils.

For flatting purposes they are used as the main vehicle,
A sufficient quantity of linseed oil must be used to bind
the pigment. It requires little to accomplish that purpose,
so that finishing coats of flatting are nearly entirely of
volatile oil. As flatting is usually done over a gloss
coat — one containing considerable linseed oil — unless
the flatting is delayed until the gloss coat has dried hard,
there will be enough tack in that to hold the flatting
thinned almost entirely with volatile oil. If, however,
one waits till it has thoroughly hardened, a small quantity
of linseed oil must be added to the flatting coat.

Spirits of Turpentine

Spirits of turpentine is the commercial term used in
the United States to designate what the painter calls
turps at the shop. In England, it is best known as oil
of turpentine, which it really is. Both names refer to the
same liquid.

It is obtained from several species of pines. That
which has been so abundantly produced in America is
derived entirely from the longleaf yellow pine of the tide-
water section of the Southern States adjoining the
Atlantic and the Gulf of Mexico. It is produced on a
large scale by scarifying the trees and collecting the
exuding gum which gathers at the wounds. This gum is
a highly odoriferous semi-solid resin. This is gathered
and hauled away to refining works, where it is distilled.

208 MODERN PIGMENTS

The volatile vapors are cooled and condensed into the
spirits of turpentine, while the solid parts remain as
rosin of many grades of goodness, according as it is
very light or dark colored — the whitest being the most
valuable.

Spirits of turpentine is the most valuable of the volatile
oils used by the painter. Its odor, while it is strong and
penetrating, is far from being disagreeable, and unless it
is used during hot weather in a close room it is not
unhealthy as are those oils derived from petroleum
distillation.

Spirits of turpentine acts promptly upon the urinary
organs, and it is strongly diuretic in action. Some men
seem to be much more readily affected by it than others
— some are so to the extent that they cannot endure to
work with it long at a time; others again have worked
with it daily for years without being detrimentally
affected by it. Persons who are troubled with kidney
diseases should be careful in its continued use. It is
not only absorbed by direct contact through the pores
of the skin, but also by the inhaling of its vapors, which
soon permeate the atmosphere of a room where it is used,
and where, as in flatting, little outside air is allowed to
enter, and then it is inhaled at every breath in large
quantities.

NAPHTHA AND BENZINE

Properties and Uses

For the purposes of painting, these two volatile oils
may be treated together. Both are so nearly the same
in composition, working qualities and odor, that they
may be regarded as the one thinning vehicle in paint
mixing. They are both derived from the distillation of
petroleum, and in early days were in very bad repute.

VEHICLES 209

They possess the properties ascribed to the volatile
oils useful in paint mixing, and described under the
heading of Spirits of Turpentine. They do not, any more
than turpentine, possess any binding properties. As
diluents of linseed oil, they are as good as and in some re-
spects better than, spirits of turpentine, and in one instance
they are not so good.

They are better, in that it takes less to accomplish the
purpose for which they are used (the only legitimate use
that can be made of volatile oils in paint), that of making
a paint more liquid — spreading better.

But, phew! The smell! That is where the inferiority
comes in. Their odor is repugnant to many persons, and
to a few it is equal to a dose of lobelia or tartar emetic.
They, too, act upon the kidneys and urinary organs, but
not in such a marked manner as spirits of turpentine,
and in addition they more than tax the stomach. For
outside painting, they are better than turpentine, for the
reason, already given, that it takes less to dilute the paint,
so that more oil can be used and applied, and consequently
the paint will not flat out so quick. It evaporates some-
what more quickly and sets the paint in a shorter time —
another advantage.

The better grades of these oils are treated with a view
to removing the disagreeable smell inherent in them, and
while thus treated they do not smell nearly as bad as
those which have not been deodorized; there is room for
vast improvement in this respect. There is hope enter-
tained of this. Spirits of turpentine is becoming scarcer
and higher every day, and, at the rate that the Southern
forests are disappearing under the ax of the lumberman,
it is only a question of a few years when the quantity of
it obtainable will be so small and its price will have soared
so high that it cannot possibly be employed, as it was by

210 MODERN PIGMENTS

the general painter. In quantity it will have dwindled
down to where there will scarcely be enough of it left to
supply the demand of the pharmacists of the world, who
all look to the United States for their main supply.

When that time arrives, — and it is plainly in sight now,
willy-nilly, — naphtha and benzine must ta"ke its place.
If completely deodorized, there will be no loss — at best,
one might as well become accustomed to their use now;
and artists, decorators, and others might as well quit
shedding tears and accept the inevitable.

Aside from their uses as diluents, the volatile oils are
powerful solvents of certain gums and resins of both
hard and soft composition. Varnish manufacturers have
been most liberal purchasers and users of them for that
purpose, and increase each year, as the phenomenal
increase in their output necessarily demands more and
more.

CHAPTER XX

VEHICLES (Continued)

Varnishes, Japans, Alcoholic Solutions of Shellac, etc.
VARNISHES

General Remarks

UNDER the general name of varnishes, many differently
constituted liquids are to be found. Naturally,
according as to how these are composed and com-
pounded, they vary in their characteristics, each being
better adapted than are the others for some particular
line of usefulness. The term varnish seems applicable
to any liquid holding gums or gum-resins in solution,
which upon the loss of its volatile parts, and upon
the oxidation and hardening of its fixed oil and
gum-resins, shows a gloss upon surfaces over which they
are applied.

Some liquids will make a varnish (when properly
treated) upon drying — as linseed oil will, after it has
been heated at a high heat — but the gloss is greatly
improved by the addition of gum-resins of various
kinds.

In point of fact, no varnishes are made thus, and all may
be said to be composed chiefly of gum-resins; the liquids
used as solvents for these may be fixed oils, volatile oils
or various mixtures of those two, or it may be alcohol as in
the so-called spirit varnishes.

211

212 MODERN PIGMENTS

Properties and Uses

Varnishes — aside from the uses for which they are
principally adapted, i.e., the finishing of surfaces with
a glossy coating, over paint put on in the ordinary way,
in graining, or over car, coach or carriage work, or over
the natural wood itself, as in hard-wood finishing, or in
enameling or japanning — they are also used as a vehicle
for the direct application of pigments. Enamel painting
depends chiefly upon their use as pigment vehicles.
Iron bed manufacturers, bicycle factories and japanning
works, use them as vehicles, and they are true vehicles
in every sense of the word, with this difference, that
the fixed oils and their volatile adjuncts, are so of their
own selves — while varnishes are not, but become so by
the nature of their component elements, which, as was
seen, are chiefly of those two classes of vehicles plus the
gum-resins which also act as binders.

The painting must necessarily partake of the nature of
its thinning varnish vehicle, some kinds of painting
requiring certain varieties of varnish for thinners, and
others, again, requiring different ones.

The varnishes which contain linseed oil as their principal
solvent and which have hard gums in their composition
— such as gum copal — are slow driers, but are elastic,
and in some degree resist the elements. Such are desig-
nated for outdoor or exposed conditions.

Then for inside work, varnishes whose main solvent is
turpentine or the petroleum volatile oils plus some lin-
seed oil for binder, will be preferably used for inside work,
as they dry hard, and being protected from atmospheric
changes and moisture they answer fairly well for the
purpose where hurry and expense are to be closely
considered.

VEHICLES 213

It is not intended in this work to give varnishes such
attention and notice as would be expected in a treatise
upon coach painting, for instance, as the only relation
in which they are of any interest in connection
with a book upon pigments is as to their use as vehicles
of them. As vehicles, their glossy properties are
secondary, — in fact, of no interest whatever even to the
coach painter, with the exception of the enamelers, who
do not varnish over their wares afterward.

To resume, then, in a few words their values as
vehicles, the following advice is given: For per-
manent outdoor work, select some varnish made
from hard gum resin dissolved in linseed oil; mainly
of this description will be found the wearing body
varnishes of the carriage trade, and some of the better
carriage parts varnishes, and the so-called spar varnishes
or outside varnishes, which are made to withstand
hardships. Some few of the best grades of rubbing
varnishes are also of this order.

For work that is not exposed, the better grades
of the so-called inside varnishes are made from
less expensive gum resins, and all of softer texture
with a larger proportion of volatile oils, and will
answer fairly well. There is a wide range between
the poorest and the best, and one must be governed
by the circumstances when selecting for certain
purposes.

Some manufacturers list varnishes especially prepared
for mixing with colors. However, if one has used a cer-
tain quality of varnish with good results, he should
hesitate to continue its use, as he is likely to have
some trouble at first with even a good new one with which
he is unacquainted.

214 MODERN PIGMENTS

JAPANS

Properties and Uses

It is a very hard matter to give a true definition of
what is really meant by the term japan, notwithstanding
the daily use of it in the paint shop.

It is a varnish, and should be classed as such and with
them. As popularly known and understood by many
painters, it means to them simply a liquid drier. To the
carriage trade and to the color grinders, it means a vehicle
for the application of paint and for the grinding of it in ;
and to the japanners and to the enamelers, a baking
varnish. In the last relation, it certainly is a varnish.

It is needless to say that japans vary as much in their
composition as they do in their qualities, according to the
formulas under which they have been made, and these
are legion.

They can be divided into three classes. The first, which
the house painters chiefly use are liquid driers, and con-
sist principally of a solvent and some oxide of manganese.
These are not varnishes in any sense of that word.

The second class, which are for grinding and applying
coach colors, are properly varnishes, and of such are the
gold sizes and coach japans, and in reality should be
classed among the medium grades of varnishes. They
make good vehicles for the purpose for which they are
used. A great variety of good, bad, and indifferent coach
japans are made, and the price paid for them is not always
an indication of their quality.

THIRD CLASS

The varieties used in baking by enamelers are made
so as to stand that operation. They evaporate under
heat, and soften sufficiently to permit the coating of paint

VEHICLES 215

to level up free from brush marks and then dry with a full
gloss. There can be no doubt as to the character of
these nor of the japans used by the radiator men.
According to the gums entering in their composition, they
are either good or bad. Manufacturers of bicycles and
enameled iron bedsteads, etc., usually immerse all their
commodities in a dipping tank and stand them on inclined
drying boards, where the surplus color runs off, instead
of hand-brushing the color.

These varnishes are probably called japan from the
fact that all the small articles of bric-a-brac found on
the market have a smooth finish, usually obtained by
what is known as japanning, by baking in ovens specially
constructed for the purpose. These articles are made to
imitate in their finish the smooth lacquering put on the
same class of ware imported from Japan and China.
The name, no doubt, was transferred and applied from
the country to the finish, and means that here. In so
far it is easy enough to understand how such varnishes
can be called Japan, but why the same name is used by
the trade for mixing varnishes of the coach painter or
the liquid drier of the house painter is one of the conun-
drums which life is too short to unravel.

ALCOHOLIC SOLUTIONS OF SHELLAC

Properties and Uses

Shellac varnish as it is sometimes called, or simply
shellac, which to many means the same thing, and spirits
shellac, as it is known in the British Isles, are all one and
the same thing. It is simply shellac, either the orange
or the white, dissolved in alcohol.

It makes a fair vehicle for pigments, where speed and
quick drying are imperatively demanded. This varnish,

216 MODERN PIGMENTS

owing to the volatility of its solvent, — alcohol, — sets very
quickly, — in a few minutes, — and in a few more it is dry
and so hard that the painting done with it cannot be
brushed over without marring it.

Owing to its setting so quickly, it is very hard to apply
properly, and it requires an expert to handle it success-
fully. Its use must be confined to hurried work, and
for that it has no equal.

The above concludes the list of vehicles used in paint-
ing,— at least those worthy of consideration.

There is a possibility of some others becoming very
useful at some future time, but their cost is now too great
to really entitle them to notice. Of this class is China
wood oil or Tung oil, which is said to possess very good
qualities. Should it be possible to acclimatize it here,
and its cost brought somewhere near that of linseed oil,
it might prove a dangerous rival; but it has never been
given the proper tests for endurance, etc., which would
warrant any one forming more than conjectural opinions
concerning its possibilities.

Correctives are used with vehicles, as was intimated;
and, again, some solids are binders to add to vehicles con-
taining no binding properties. The next chapter will be
devoted to these.

CHAPTER XXI
WAXES

BEESWAX

Properties and Uses

WAXES are not used as vehicles in painting, — as are the
liquid vehicles, — owing to their property of solidifying in
a few moments, at ordinary temperatures, as that makes
it impossible to melt them, mix them with pigments, and
apply the paint so mixed before it would have cooled and
become so hard that nothing could be done with them in
the ordinary way.

Encaustic painting, however, was known and prac-
ticed long before the present system of painting was so
much as dreamed of. The ancient civilizations made use
of it freely, and some of the work of their now unknown
artists is occasionally found in as fresh and well-preserved
a condition as when it was first applied centuries ago.

There is still some encaustic work done, but in an
amateurish way, as artists much prefer the use of linseed
oil to the slow and difficult method of applying paint by
the encaustic process.

In encaustic painting the colors are first put on with
a liquid, — water will answer as well as any, — and after-
ward the wax (when it has been melted by heat) is flowed
over it. A flat, hot iron is used on it to obtain a per-
fectly level surface. The finish is certainly very pleasing;
and the colors, being hermetically sealed from contact

217

218 MODERN PIGMENTS

with air, are not injuriously acted upon. It stands to
reason that for the finishing of interiors at least such
work must be permanent.

Beeswax was probably the form of wax used in the
encaustic painting of the ancients, although they were
also acquainted with the waxes derived from vegetable
substances.

Beeswax is used for many purposes by the house
painter, — in fact, all forms of waxes are, — not so much
as a vehicle as it is for the finishing of floors or wood-
work, and large quantities of it are annually consumed by
the paint trade.

As it comes from the melting pots', it usually is of
yellow, but often is found of a brownish tone; tlje latter
being impure, it must be rectified and bleached before it
is fit for the best work. The process of bleaching, also
raises its melting-point and hardens it.

Beeswax is a vegetable product gathered by bees from
plants, and is not an animal production as some errone-
.ously suppose it to be. It is permanent for interior
work, but when exposed to the inclemencies of the
weather upon the outside, it is partially destroyed by
oxidation.

VEGETABLE WAXES

Characteristics

Many plants produce wax, and in South America,
especially in Brazil, it is gathered from the leaves of
Copernica cerifera, where it occurs in thin sheets. It is
a regular article of commerce in that country. In China
and the Thibet there is an extensive trade done in vege-
table wax. Its melting-point is high, 185° F. But for
its limited quantity and consequent high price, it would

WAXES 219

be more extensively used here; it makes a hard wax.
Vegetable wax is used for all purposes indicated under
the heading of beeswax.

PARAFFIN WAXES

Characteristics

Paraffin waxes are the' product of petroleum distillation
and vary very much. Most of them have such a low
melting-point as to unfit them for encaustic painting or
any other purpose of the painter. Their melting-point
ranges from 105° to 180° F. The very highest qualities
of them are very good, and in one respect at least render
them superior to the vegetable waxes in that they are
not so readily acted upon by the volatile oils, nor will they
mix with them as those do. Such will consequently
make excellent binders for pigments for encaustic work
or for the waxing of floors where their hardness is greatly
in their favor. It is also useful to add to such very heavy
pigments as quicksilver vermilion, as it helps to prevent
the separation and precipitation of that pigment when
mixed in linseed or poppy-seed oils, but small quantities
of it should be used for such a purpose.

While encaustic painting is commonly done by using
the wax as a covering for the colors previously applied,
and not as the vehicle to convey them to the work, yet
there have been some very fine pictures painted where
it was used as the vehicle for the mixing of the pigment
and of its application. This requires great skill, and is
not likely to ever become popular, as both the work itself
must be kept warm as well as the vessels containing
the melted wax and pigment.

CHAPTER XXII.

SUBSTANCES USED IN BINDING PIGMENTS
GLUES

General Remarks

THE substances whose description is attempted in this
chapter are not vehicles themselves, being solid sub-
stances, but are adjuncts to liquid vehicles which do not
possess any binding properties within themselves capable
of fastening the pigments for the application of which
they serve as a medium to surfaces and which other-
wise through their lack of adhesiveness would fall down,
wash away, or blow off from them upon on the least
provocation.

In distemper painting, for instance, water is the vehicle
used, and no arguments are necessary to show that paint
applied with it would have absolutely nothing to hold
it after the water had evaporated. These binding sub-
stances are added to hold the pigments to their place, and
they become parts of the paint itself after the vehicle has
evaporated.

Among the agents which are principally used for this
purpose, glue easily holds first place, not that it is the best
of all, but because it is the most economical as well as
the handiest of any on the list. It is by long odds the
one binding substance which is most universally used,
and the quantity annually employed for the purpose is
something enormous.

220

SUBSTANCES USED IN BINDING PIGMENTS 221

It is not only employed by painters in the preparation
at the home shop of distemper colors, but the numerous
concerns which have sprung up within the past twenty-
five years with ready-prepared water paints or kalsomines
or anti-kalsomines of all sorts, prepared from gypsum,
etc., — which are all ready for use by the simple addition
of either hot or cold water, — these use incredible quan-
tities of it in the compounding of said ready-prepared
distemper paints. This preparation of wall water-paints
has grown up into a great industry and is extended every
year, and they are found for sale in every general store in
the land. They are uniform, handy to use, and usually give
better satisfaction than that which the average painter
is able to prepare for himself. The above is not said in
order to discourage any one from mixing his own com-
pounds, but as a statement of fact. There is no doubt
but that any intelligent painter can mix a batch of dis-
temper colors just as they ought to be; but although
this is simply done, it must be done just right. In the
hurry, which is usually the condition existing during the
busy season of the spring, trifles are forgotten or dis-
carded for want of time. Many a painter who has been
too busy to properly prepare a batch of distemper color
to be sent out on a job, sees it go out of the shop door
with misgivings as to its future. Many an eyesore and
heartache might have been avoided by the use of a well-
prepared water paint which could have been sent out to
a job without loss of time and saved a good bit of worry.

Properties and Uses

Glue is an animal product, obtained by the boiling of
hoofs, bones, cartilaginous parts of carcasses, hides, hide
trimmings from the tanneries, and even parts of flesh.
If the treatment is done at a temperature above the

222 MODERN PIGMENTS

ordinary boiling heat, the process is greatly hastened.
The various processes and manipulations are all simple
and well known, but too lengthy to give, and can be
summarized thus: Glue is the residue which remains by
boiling the animal parts referred to and afterward drying
the same when it has been cleansed of impurities by
various processes of clarification, etc.

Its binding properties are due to two distinct yet
similar compounds, gelatin and chondrin. The chemical
composition of those bodies is carbon, hydrogen, nitrogen,
and oxygen in various combinations. Both substances
are entirely soluble in hot water and are coagulated by
tannin. Cold will also coagulate them, hence the well-
known property which is exhibited every time one mixes
a pail of kalsomine, — it "jells" when it cools, which makes
it work smoother and makes it easier applied than before
coagulating.

Glues are thrown in three different classes, according
to the material that was used in their preparation.

1st. Hide glue, made from skins, ears, tendons, hide
trimmings from the tanyards, and similar offal.

2d. Bone glue, from hoofs, feet, bones, joints, and any
osseous offal.

3d. Fish glue, made from the bladders, entrails,
scales, and bones of fish.

All are well aware of the great difference in the strength
possessed by various glues. This depends upon the
material of which they have been made, and in a lesser
degree upon the manner of their preparation.

Hide glues are the strongest of any, and possess the
greatest tenacity. Bone glues are the weakest. It is
difficult to make a glue salesman own up that any
of his samples are bone glue, but some of them certainly
are. Fish glue, especially that made from Russian stur-

SUBSTANCES USED IN BINDING PIGMENTS 223

geon stock, is very strong. Some of the fish glues made
from the bladders are not only very strong, but as clear
as glass, offering no obstacle whatever to the passage of
light rays, — any more than would so much crystal. Isin-
glass is only a very fine form of such fish glue. The
bone glues usually furnish that form of glue known
as gelatin.

Glues range in color from that which is light and trans-
parent to the dark brown stinking refuse, which forcibly
reminds one of being very near a spot where animal
matter is decaying.

That which is prepared for the binding of kalsomine or
water colors is known to the trade as kalsomine glue. In
shape it is in thin sheets, which are broken up in small
pieces before packing in barrels. There are many quali-
ties of it. That which breaks with an elastic fracture
and is of a light creamy tone is usually good. If it
is very white and opaque, the chances are that it
has been weighted with some adulterating sub-
stance. These white weighted glues are not as
economical nor as satisfactory as those of a creamy
semi-transparent tone.

Glue comes also in a pulverized form, ground up in
small, angularly shaped particles, and it is to be found thus
in all grades from poor to good. Usually ^these do not
run as strong as the regular kalsomine glues do, but the
better qualities answer the purpose well enough. The
ground glues dissolve more readily than those that have
not been broken up, and the thin ones of the kalsomine
glue sorts dissolve quicker than the thick glues. Glue,
however, of any and all shapes, can be used for the pur-
pose of binding pigments in distemper work. It is only
a question of convenience, saving of time, and of a knowl-
edge of the strength that they possess, as without that

224 MODERN PIGMENTS

it will be impossible to properly gauge the proper quan-
tity of it to use for the binding of a given weight of pig-
ment. Glue has the property of absorbing moisture and
of retaining it when it comes in contact with cold water,
but it is not dissolved by it. This well-known pecul-
iarity is made use of by painters to hasten its solubility
and to melt it. The glue is soaked in cold water over
night. During that period, it will have absorbed several
times its own weight of that liquid. It will then be
swollen much above its normal bulk and softened in
texture. This soaked and swollen glue, when placed in
a vessel over the stove, will readily dissolve at a low heat,
and thus will save much time and worry in melting it in
the dry state, as then it requires constant stirring and
much more heat besides care, or it will burn at the bottom
of the vessel. When melted, it is ready to mix with the
pigments, which should always be done before it has had
time to cool and become jellied.

In warm weather, putrefaction commences early in
colors thus prepared, and unless one has a refrigerator
for the surplus that cannot be used the same day, it will
be better and pleasanter to mix no more than will be used
up clean that day.

To lessen the tendency to putrefaction, a few drops of
carbolic acid or eugenol (oil of cloves) may be added.
This will retard fermentation, but will not prevent it.

GUM ARABIC

Properties and Uses

Gum arabic is probably the best binding substance
known for water colors, and if it is given only second
place on the list, it is not because it does not deserve to
have the first, but because its much greater cost and

SUBSTANCES USED IN BINDING PIGMENTS 225

also the greater care and difficulty in its use render
its universal employment impossible; and also on ac-
count of another reason: if gum arabic was used to
the same extent as glue is for binding pigments, there
would not be enough of it in the market, and its
cost would soar so high as to put it out of commission
at once.

Gum arabic is a true gum, and consequently it is of
vegetable origin. It is produced from several species of
acacia. That best known is supposed to be produced
from Acacia Arabica, and its name is derived from that;
but in reality it is derived from Acacia Senegal, which is
much more common, and the gum arabic of commerce is
chiefly obtained from that variety.

Its composition is a mixture of the salts of arabic acid,
these salts being of three bases, — potash, lime, and mag-
nesia with water.

The better specimens are nearly all free from color,
clear, and nearly if not wholly soluble in water, and the
solution clear.

Gum arabic dissolves very slowly in cold water; boiling
water must be used in making solutions. It should be
pulverized to facilitate this, as it takes a long time to dis-
solve the lumps. After the solution is made, it should
stand for a day, and the clear liquid poured off, when the
undissolved impurities will be found at the bottom and
should be left undisturbed. It should be prepared before-
hand, so as to have it at a moment's notice. It will be
well to guard against any fermentation by the addition
of a few drops of eugenol or of a lump of camphor
which will float upon the top; this will prevent it from
souring.

Being so much more slowly acted upon by cold water
than the glues, and being so much less subject to putre-

226 MODERN PIGMENTS

faction than animal matter, its use is indicated for dis-
temper, fresco, and all good water-color work. For
artists' use in water colors, it is indispensable.

The above two substances, i.e., glues and gum arabic,
are the two most important substances as binding agents
for distemper colors. There are a few other substances
used, but to so limited an extent as to deserve little
more than passing mention.

These have been grouped below, and consist of starch,
dextrin, honey, molasses, sugar, and glycerine.

STARCH

Properties and Uses

Starch is a substance well known to everybody,
and is derived from the cereals and the bulbous roots
of plants, as potatoes, yams, etc. Starch mixed
with cold water into a stiff paste, and in which
hot boiling water has been poured until it has become
stiff and unctuous, has been and is occasionally
used to mix pigments and apply them to surfaces.
Its use for such a purpose can only be tolerated upon
the plea of dire necessity, when no other and better
binders are procurable, and cannot be recommended
even for the cheapest kind of work.

DEXTRIN

Properties and Uses

The Dextrin of commerce is derived from starch. While
its adhesiveness is greater than that substance, it is so
much weaker than that of either glue or gum arabic,
that its use is very questionable as a binder for distemper
painting. It has another fault, in that it softens in warm

SUBSTANCES USED IN BINDING PIGMENTS 227

weather; and those who have had to do with sticky enve-
lopes and stuck-together stamps will know enough not
to want to fool with it.

As a corrective, used in small quantities with glues, it
is said that it will prevent the suction of hot walls and
keep the color from striking in too rapidly.

HONEY, SUGAR, AND MOLASSES

Properties and Uses

Honey, from its soft condition at all times, is not fitted
for the binding of colors; molasses is similarly constituted;
while sugar is a solid which by the addition of water can
be brought to the consistency of syrup. The three
possess about the same properties, and are too weak for
the binding of water colors. As correctives to be used
with distemper colors mixed with glue, they are fre-
quently resorted to for the same purposes as mentioned
under the heading of dextrin. Honey is also used as a
corrective in the preparation of artists' water colors in
the form in which they are so popular now, that of moist
pans. It is also used in very limited quantity in the
hard cakes to prevent the gum arabic in their compound-
ing from becoming too brittle and crumbling to pieces.
As honey usually becomes crystalline, and in that condi-
tion is as useless as granulated sugar would be, it is
treated to prevent its crystallization, and has its
dextrose removed. This is accomplished by mixing
it with four times its bulk of alcohol and keeping it
agitated every few hours for two consecutive days;
then the pale alcoholic solution is filtered. It is
fit to use in that condition, or the alcohol may be
recovered by distillation, and the residue in a syrupy
condition may be used instead.

228 MODERN PIGMENTS

GLYCERINE

Properties and Uses

Glycerine is obtained from oils and fats. Many of the
large soap works produce it as a by-product. It is of the
consistency of a thin syrup and has a sweetish taste. It
attracts moisture readily, and will absorb more than one
third of its weight from the atmosphere. That which is
found in commerce has always some water in its com-
position. This can be readily detected by its specific
gravity and the percentage of water computed from the
variation of that which it shows and that which it ought
to have. Its great attraction for water really makes it
superior to honey in the manufacture of cake and moist
cake water colors, and many are beginning to use it for
that purpose.

It is also very useful to add to distemper colors and
kalsomine for wall-work and for rooms where the plas-
tering is in that condition which is known as hot. It will
greatly facilitate the application of the paint into which
it has been added in the proportion of four to six fluid
ounces to the pail of color (about 2J gallons). Its use
has saved many a man from profanity.

CHAPTER XXIII

DRIERS AND SICCATIVES

General Remarks

It has been noted in the descriptions of the various
pigments that some of them were called non-driers.
The pigments themselves, being powdered solids, never dry
any more than they do when ground up with oil to a
paste. The term, therefore, does not apply to them
really, but to the linseed-oil vehicle with which they are
mixed, and refers to the action of the pigment upon the
oil. It was also noted that some other pigments on the
contrary aided the drying of the fixed oils.

The main reason for the non-drying of pigments is that
some contain fatty oils which do not dry; there are also
other reasons which were noted under each head. Again,
it was noticed that the lead pigments which were
oxides of that metal, and that pigments also which con-
tained oxide of manganese in their composition, hastened
the drying of the oils.

The oxides of lead are all very good driers, but also
some of the other salts of that metal and acetate of lead
are especially so; even white lead itself possesses that
property to a good degree but not in such proportion
as some others. It will usually dry raw linseed oil in a few
hours outside, without the addition of artificial driers
unless the weather is cold and the atmosphere too humid.

In describing the drying of linseed oil, it was said that
the heating of the linseed oil of itself rendered it more

229

230 MODERN PIGMENTS

siccative, so that even subsequently, after it had cooled,
it would still retain some of its thus acquired drying
quality.

Linseed oil would dry naturally when mixed with inert
pigments, as these exert no influence upon its drying one
way or another; and with the pigments, which will aid
its oxidation the more quickly, as these part with their
oxide more rapidly or liberally, and when mixed with the
non-drying pigments much more slowly or not at all,
according to the composition of the non-drying colors.
If the temperature could be depended upon to remain
above 70° F., and the barometer at "Beau Fixe,"
and only pigments mixed with linseed oil which
were not inimical to its natural drying, there would be
but little need of driers; but, unfortunately, there can be
no dependence placed upon it. Neither the thermometer
nor the barometer ever remain very long where the
painter would like them to be, being proverbially fickle,
so, by the use of dryers, he must guard against the
possibility of having his work destroyed by changes which
are likely to come at a moment's notice.

Again, in interior work, the women folk are ever hurry-
ing up the poor painter, and ever threatening all sorts of
evil to him, even to threatening him that this is to be the
last job for him there, if he does not put in a little more
push to his hastening along with it, when he is doing all
that possibly can be done, and more, for the real good of
the painting; or in business houses or stores, where the
painting has to be done at night, so the paint may be
dry in the morning, there is no other alternative left to
the painter but that of using siccatives in his paints, no
matter whether this is good for it or not.

There is no doubt but that much of the short life of
paint complained of is due, in part at least, to the hurried

DRIERS AND SICCATIVES 231

drying of linseed oil, which burns it up — that is what fast
drying means. Where the drying is slow and natural,
the conversion occurs without violence. Then the paint
will stay on much longer and remain in good condition
without checking all over from lack of adhesion and
elasticity.

BOILED LINSEED OIL

This is the simplest of the siccatives. The heating of
linseed oil renders it more drying. Boiled oil, when the
boiling has been done, as it usually is, with the oxides of
lead or manganese present during the process, renders it
still more drying.

How those substances are capable of imparting oxygen
to linseed oil without losing any of it themselves is not
well understood. One thing is sure, if a given weight
of those oxides be placed in a bag with the oil and all
boiled together, these bags may be taken out and the
linseed oil carefully washed away with benzine, and the
oxide powders dried and weighed, when it will be found
that they have not lost any of it by the operation, but
the linseed oil will have absorbed oxygen through their
agency some way.

As a siccative, boiled oil has its uses even for outside
painting, but it is seldom used for that purpose, probably
because the specially prepared liquid driers or japans
are more powerful siccatives and smaller proportions are
necessary to accomplish the purpose of drying the oil.

LIQUID DRIERS

General Remarks

Manufacturers of varnishes usually prepare siccative
compounds for the drying of linseed oil. They are sold

232 MODERN PIGMENTS

under many names, such as drying japans, liquid driers,
liquid siccatives, and many fancy proprietary names.

The solving medium used in their preparation is really
of little moment, whether it be linseed oil, spirits of
turpentine, naphtha, benzine, or mixtures of these. The
quantity necessary to dry a given amount of linseed oil
is so small that their presence in the oil can exert little
influence other than that which is expected of them —
the drying of the oil. An undue quantity added to lin-
seed oil will injure it, but then that would happen no
matter what the solvent might be.

LEAD OXIDES

The action of these has already been noted, as, for
instance, when boiled with linseed oil, etc. All lead
siccatives have one drawback that they all hold in com-
mon, they subject the oil, or rather the pigments mixed
with it, to the action of sulphuretted hydrogen.

This is not so noticeable in the liquid driers as it is
in the paste driers, when the lead oxides themselves
become a part of the paint.

The paste driers will be noted further on more fully.

Liquid driers are very seldom, if ever, made from the
lead oxides, for the very good reason that the

OXIDES OF MANGANESE

are much better adapted for that purpose. When made
with these, there is no danger of any further discolora-
tion taking place, outside of that which is produced
immediately after the mixing of the liquid manganese
drier with the paint. The greatest drawback is their
dark brown color. If, however, the brown borate of
manganese is used in the preparing of the liquid drier,
the dark tone of the drier will be reduced to a minimum,

DRIERS AND SICCATIVES 233

The manganese driers are such strong driers that, if
they have been well prepared, but little of them need be
used, and that little will influence the drying of linseed
oil a long way.

There is absolutely no excuse for using the large quan-
tities of liquid manganese driers many painters do. It
then becomes dangerous, for it burns the paint, and, in
excessive quantities, it will defeat the purpose for which
it is used at all — the drying of the oil. When will the
careless painter learn that a little manganese drier will
accomplish the object of drying oil much better than the
larger quantities of it. Strange as the above may sound,
it is not the quantity used that causes the oil to dry
faster, for it will take it up only as it needs it — at its
convenience, nor will it take up more than the needed
amount. Another strange fact, hard to explain, is that
when excessive quantities are used the very object of
quick drying is defeated, as then it seems rather to pre-
vent than accelerate it. One large tablespoonful of a
well-made standard average strength liquid drier is
amply sufficient for any ordinary pail holding three
quarts of paint ready thinned for application. This will
dry all ordinary mixtures where white lead is the base
of the paint. For Vandyke browrn and lamp black, half
a pint to the gallon of linseed oil will be found suffi-
cient — those two pigments being the most anti-drying
ones on the list.

PASTE DRIERS

The oxides of lead, we have already seen, affect white
lead compound and others even more, which are not
affected by sulphuretted -hydro gen gases, which, when
they are used, are affected by their presence.

Formerly large quantities of acetate of lead paste
driers were manufactured, but their defects under

234 MODERN PIGMENTS

unfavorable conditions — specking and coming out as an
efflorescence — have greatly reduced their use. Under
that form and style they are still used in certain localities.

Paste fillers are made and prepared according to pro-
prietary formulas, so that what might be a good one
made by one firm will not necessarily need to be a recom-
mendation for some one else's make, simply because it
is put up in that form. Acetate of lead is the base of all
light-toned ones. They are used for very light tints and
whites. Many an artist has had to rue the day when he
was tempted to use them, as they are chiefly composed, as
was said, of acetate of lead, or may also contain white
oxide of lead or litharge, which, however, darkens it some.
Aside from subjecting the painting to the action of sul-
phurous vapors, deteriorating and specking or efflores-
cing, there are other injurious chemical changes affecting
them.

Sulphate of zinc drier in paste form is a fair drier for
zinc white, but of little value when used in connection
with any other pigment.

Borate of lime and borate of zinc also make useful
driers for zinc paint.

Some paste driers are now made with borate of man-
ganese as the chief ingredient in their composition. Such
will be found more effective and more valuable, even if
they are a trifle dark, than the other varieties of paste
driers, but they are not as advantageous as the liquid
driers. They require to be carefully thinned out before
mixing with the paint, and for that reason will never
become popular. It is a waste of time to triturate them
and thin them for use, which, when done, puts them in
liquid form and makes a liquid drier of them after
all. Why not procure that in the first place and save
all the bother?

CHAPTER XXIV
THE COMPOUNDING OF PIGMENTS.

THE compounding of pigments changes the color of
each, imparting to the others a part, and in return receiv-
ing a part of theirs, so that the completed mixture becomes
a new color different from that of the pigments produc-
ing it, but which partakes of the character of each one
of them in some degree.

THE PRIMARY COLORS

Of colors proper there are but three. These three are
called the primary colors. They are the following:

Red, Yellow and Blue

White itself is but the product of a perfect combination
of the three primaries, black being simply a negative of
all color.

SECONDARY COLORS

From the combination of two of any of the primary
colors together are made the secondary colors, and these
are as follows:

Purple, Orange and Green

They are thus produced:

Red and blue = Purple.

Red and yellow = Orange.

Yellow and blue = Green.

235

236 MODERN PIGMENTS

TERTIARY COLORS

From the union of two of the secondary colors comes
a third set, the tertiary colors which consist of the
following:

Olive, Citrine and Russet

They are derived in this way:

Purple and green = Olive.
Green and orange = Citrine.
Purple and orange = Russet.

Further mixtures of these produce the neutral tints.

From the above three primaries, three secondaries and
three tertiaries, with the addition of white and black,
are produced the hundreds of thousands of varied tints
which form the kaleidoscope of infinite variety adorning
everything animate and inanimate upon this mundane
sphere.

It is regrettable that no more space can be devoted to
the study and notice of color harmony, but this would
unduly enlarge the volume, and it is not strictly within
the subject matter. The color student is therefore advised
to procure some of the excellent treatises which deal
with this subject as their primary object. There is
nothing more interesting than the study of the phenom-
ena of color. It will greatly help the student, not alone
in that it will help him to mix tints properly, but also in
the higher object of becoming master of color effects,
which is a faculty that few otherwise very good painters
possess, and which would be worth to them in after life
many times over whatever effort in time and money they
may have spent in acquiring a good knowledge of color.

Expert colorists are in good demand at any reasonable
figures which they. may demand for their services.

THE COMPOUNDING OF PIGMENTS 237

For the making of tints, a base is used upon which to
build it. The base is that pigment which enters the com-
pound in the greatest quantity. If a white, — and that
is usually the base of all light tints, — it is either white
lead or. zinc white, used alone or together in any propor-
tions, and still other whites may be added to them as
correctives if desired.

The rules given below are formulated for guidance in
the preparation of tints, with linseed oil as the vehicle,
and for pigments which have been ground to a paste
in the same vehicle. These same rules will apply to the
mixing of pigments and the making of tints from them
in any other vehicle, japan, varnish or water, with what-
ever slight alterations made necessary by the different
nature of those liquids.

1. THE BASE

The base, as was said before, is the principal color of
the tint. Tints usually, but not always, are lighter
tones of those of the pigments used in compounding
them, so white must be used -to lighten them up. It
thus becomes the principal color or the base upon which
the tint is built. It may be any white pigment, or
combination of them; but to simplify matters, and also
on account of its being the pigment in chief use for the
purpose, when a white base is designated hereafter it
it will be called white lead, no matter if it is that or any
other white that one may prefer to use.

In some few cases, however, where great purity of
tone is necessary, and for certain kinds of interior work,
zinc white should be substituted. With these explan-
ations one cannot greatly err. It will be an easy matter
to substitute zinc for lead, when it is well understood
that the white lead base that is indicated in the next

238 MODERN PIGMENTS

chapter does not stand as meaning that especially, but
only a white base as the predominating pigment.

The white lead or zinc white or other accessory whites
must have been broken up, as is called the operation of
taking it out of its original package or keg in which it
was placed at the factory — and thinning it with sufficient
linseed oil to make a rather stiff and smooth paste. It is
not such an easy matter as it may look, to a novice, to stir
up the lead and to get it into a smooth uniform mass
free from lumps. It is simple, but it means hard work,
requiring strength and effort to perform it properly.
Some use a little turpentine with the oil, to make it break
up readily, and the small quantity required will not
harm it for any purpose of outside painting. If possible,
the breaking up should be done the day before prepar-
ing the tints; if left over night many of the small lumps,
which seem to defy the paddle and constantly escape it,
and which are a cause of mental irritation, and thereby
of profanity, become soaked up by the linseed oil when
left in contact with it over night, and the next day the
mass is more easily brought to a uniform smooth paste.
The tub or tubs used for the breaking up of the lead
should always be ready to furnish the base in just the
shape described, as it will be found much better than
freshly broken up lead for the purpose of preparing
tints. Of course, it is not absolutely necessary that it
should be broken up ahead of the time it is needed, but
it will be found better, and the better way is what the
author is trying to inculcate.

2. THE COLORING PIGMENTS

These, too, should have been previously broken up by
the gradual addition of small quantities of linseed oil.
When the pigment has been beaten up with the oil, and

THE COMPOUNDING OF PIGMENTS 239

has absorbed all the oil, forming a smooth paste of uniform
texture, more is added and triturated with it, till again
that is absorbed, and a liquid is obtained which pours out
easily — as thin as one would wish to apply with a brush.
It is only when in this condition that the coloring pig-
ments can be added to the base safely, as otherwise they
will not incorporate with it with anything like uniformity,
and the tint may be streaky, which is an abomination
and a sure sign of the incompetency of the tint mixer.

3. MIXING THE TINTS

The pigments must be added slowly to the base, so as
not to overshoot the intended tint. It is an easy matter
to add more pigment to the base, if it is needed, to bring
it to the intended tint, but it is impossible to take it out
if the addition has been overdone. This overdosing is
called, in painter's parlance, drowning the miller.

Tints made by the simple addition of one coloring pig-
ment to the base are readily handled by following the above
directions.

MIXING COMPOUND TINTS

If more than one coloring pigment is required to pro-
duce a given tint, the first in importance in the mixture
should be added to the base up to a point just short of
that which it is thought its due proportion should enter
into the compound. The next one in importance should
then be added to the base, and that, too, stopped short of
that which it is thought it should be, and the same process
continued for each pigment entering the compounding of
the tint. After the mass has been well stirred, and has
become uniform throughout, it will then be an easy mat-
ter to add a bit more of this or that color, if t'here is need
of it, to bring it to the exact shade of the tint that is to
be matched.

240 MODERN PIGMENTS

- If one has been careful to stop short of the quantity
thought to be required, as is easily seen, it will be readily
remedied; but if, on the contrary, one has not stopped
in time, and has overdone it, putting too much of the
pigment in it, then the mending will be more difficult.
It will require, in the first place, an increase in the quan-
tity of the base, proportionate to the excess of coloring
pigment used over and above the right amount, so that
one will be forced to mix up a larger quantity of the tint
than was intended or may be required, which means a
loss.

If one has poured in too much through accident, and
is aware of it, it is sometimes possible to dip out the color
so poured in, or the most of it, before it has been mixed
with the base; it will then not be necessary to add
much, if any, of the base color. The waste is then
reduced to a minimum. Then proceed to thoroughly mix,
after which add the other coloring pigments, as directed,
and lastly a portion of that which was dipped out — just
so much as is needed to bring the tint to the desired
shade. The remnant will be so small a loss, that, in com-
parison with the other waste mentioned, it will be hardly
worth speaking about.

PREPARING TINTS READY FOR USE

When a tint has been compounded to the perfect satis-
faction of the mixer, as when the lead has been well
broken up and used, as it should have been, in the form
of a very stiff paste, and if the tinting pigments have
been thinned well, so they could be easily incorporated
with the base, and the whole has been well stirred up so
that the paste is of a uniform consistency throughout,
it will be found rather stiff — much too stiff for application
with a brush. But the condition it is in then is just the

THE COMPOUNDING OF PIGMENTS 241

right one for transportation, as it can be dipped out into
stock pails and transferred to the job where it is to be
used, without any danger of its slopping out, as it would
surely do had it been thinned out to the point needed
for its application.

It is, of course, impossible to give very definite direc-
tions about the thinning, as circumstances vary so much
that the experience of the man behind the brush must
be used here. No directions, other than the most com-
monplace ones, can be given, i.e., thin out more for first
and second coats than for third, and more all around for
spongy surfaces than for such as have little or no pene-
tration.

The above directions will suffice to enable anyone to
mix tints properly — in oil.

For coach painting, the same care must be exercised
as directed for tints made in linseed oil in adding the
coloring pigments to the base, the main difference being
in the thinner, which is either japan or varnish and
volatile oils. There is little, if any, compounding of tints
in coach painting, the colors used for that work being
self ones, or, if compounded at all, that is usually done at
the factory.

For distemper painting, the pigments coloring the
base — which is usually whiting — should be mixed
separately as for oil colors, only that they should be
made more fluid ; otherwise , all that was said before
applies to them also. The thinning fluid being water,
instead of linseed oil, japan, or varnish. After the tint
has been finished to the satisfaction of the mixer, the
melted glue or the dissolved gum arabic can be added.
It is much more difficult to tint shades up to a given
sample in distemper than it is in the preceding vehicles,
for the reason that pigments mixed in water do not

242 MODERN PIGMENTS

appear the same as when dry, which in oily mediums
they do. In water they appear very much darker than
they are after drying. There are no exceptions to that
universal peculiarity, so that a tint mixed to the exact
shade of a dry sample, when first applied, would be entire-
ly too light when dry. The tints should be made very much
darker than the sample to be matched, and a small patch
should be painted over a piece of paper, and the same
placed in a warm sunny spot or over a stove so the water
will evaporate quickly, and, when dry, the tint can then
be compared to the sample, and if not deep enough more
of the tinting pigment must be added until the tint has
attained the same tone as that of the sample. This may
require several times testing it, by drying it upon the
piece of paper, but it is the only safe way, and any
other method would be but guess work.

It requires considerably more experience on the part
of the mixer to hit a tint just right in a quick way. Few
men can fall into it at once. In time, the experience
gained by many former failures will gradually work up
into intuition, for that is what it seems to the man who
has tried it a few times but could not do it.

CHAPTER XXV

A LIST OF SOME OF THE PRINCIPAL TINTS AND How TO
MAKE THEM

General Remarks

IT is deplorable that the English language has no
well-defined nomenclature to designate tints. As other
languages have not got any either, it is not behind them
any in this regard; but it is deplorable nevertheless.

If one is inclined to doubt this, let him procure the
color cards of a dozen manufacturers of mixed paints,
where the tints are known and sold by name, as well as
by number, and these names printed under the tints.
It will be found upon inspection that it will be rare if any
two out of the dozen look alike. This is especially true
of the neutral tints, or those tints which are neither
primary, secondary, nor tertiary. Owing to this lack of
uniformity, some persons may think that they have not
been successful in obtaining the right tint if they get
something which does not come up to their conception
of what the tint ought to be, and may think that the
directions given as to how to make them are wrong,
or that the colors used in the making were off; all but
the right conclusion perhaps — that what they call a
gray may be somebody else's drab. If he follows the
directions for making a gray, and his own ideas of a
drab being that the gray fits them, it will certainly be
a hard matter to convince him that he is wrong, because
there is no accepted standard recognized to settle it

243

244 MODERN PIGMENTS

beyond dispute. Again, if the directions be given for the
making of a sage green, and the tint happens to be what
he conceives is a myrtle green, or an apple green or a light
olive, who will say that he is wrong? Surely, when
well-trained men differ so widely among themselves, how
can others, who have only given the study of color the
most superficial examination, be expected to do better ?
Nature itself varies exceedingly, and tints which are
named after the prevailing tones of green of certain
trees or plants are bound to form a subject of endless
and profitless controversies as to what is the proper tint.
Take instances, outside of the vegetable kingdom, out
of that of animals : Peacock blue — where is the standard
for that? Let anyone undertake to furnish one, and out
of a dozen men, at least ten would demur to it! If the
whole dozen undertook to furnish the standard, there
would be precisely twelve supplied.

So, when directions are given for the making of such
far-fetched named tints that fashion has given birth to,
such as baby elephant's breath, cataract's mist, etc.,
would many be found sufficiently aesthetic to forthwith
fall into the idea of it, or, if they did, would they coincide
as to the proper tints to represent them?

These precautionary words are necessary to warn the
reader that he must not expect too much (or the impossi-
ble) from the general directions given for the compound-
ing of tints by name. The quantity, by weight, of pig-
. ment to be used in producing them has been left blank
for the very purpose of enabling the mixer to suit himself
if possible as to the depth, and in more than two pig-
ment compounds to some extent as to the tone. This
will give the mixer a chance to use some judgment of
his own, and if he has noted the direction given, not to
drown the miller. He will have the tint light enough so

THE PRINCIPAL TINTS 245

that he can add more of the coloring pigments named
to produce the tint of such depth and tone as he requires
it to be.

There is still another very important reason why
weights are not given. It must have been made very
plain to the readers of this treatise, who have followed
the descriptions given with each pigment, that there is
a vast difference in the strength of coloring matter con-
tained in a given weight of various samples of most of
them. If one man took a recipe made up in pounds and
ounces he would obtain a tint that would bear no resem-
blance to that obtained by the very same recipe in some
other locality, where the coloring pigments were made up
by another manufacturer. Thus, if a recipe should say:

Take White lead . . . . . . . . 20 pounds

Venetian red 3

Medium chrome yellow . . 1 "

If operator No. 1, should use a pure chrome yellow and
a good-toned Venetian red; operator No. 2, of the same
town, using a chrome yellow, containing but 20 per cent
of color, and an indifferent Venetian red, would have an
entirely different tint, and it would be due to the recipe
giving precise weights. Had the same been left blank,
the chances are that the difference would not have been
so great — at any rate, the mixer would have had some-
thing nearer to his liking.

LIST OF PRINCIPAL TINTS

For the purpose of easy reference in the finding of any
particular tint, they have been listed alphabetically.

The base pigment, or the principal one of the com-
pound, is invariably named first. The other coloring
pigments are named in the order of their importance

246 MODERN PIGMENTS

in the make up of the tints. Therefore, of the last,
frequently but a very small portion need be added.
As far as possible, where a simple tinge or reflection of a
color is needed this will be indicated :

Acacia. Lamp black for base ; color it up with Indian red and
tinge with Prussian blue.

v Acorn Brown. Similar to chocolate which see — but lightened
with white lead.

Alderney Brown. Lamp black; orange chrome yellow; Fr.
ocher; white lead.

Amber Brown. Burnt sienna for base; add orange chrome
yellow, burnt umber, a trifle of lamp black, lighten shade to
suit by adding white lead.

Amaranth. Tuscan red and vermilion in about equal parts
for base; add enough ultramarine blue to suit shade of it wanted.

Anemone. Vermilion red for base; Prussian blue and a little
black and white lead.

Alabaster. White lead for base. Give it a very faint tinge
of medium chrome yellow.

Apple Green. White lead for base; add light chrome green
and orange chrome yellow.

Antique Bronze. Orange chrome yellow for base; add ivory
black ; lamp black can be substituted, but the shade will not be
so rich.

v; Apricot. Medium chrome yellow for base; Venetian red, car-
mine lake, if light shade is wanted lighten it up with white lead.

Armenian Red. Bright Venetian red for base ; lighten up with
French ocher.

Ash Gray. White lead for base; tinge with lamp black, add
a bit of French ocher.

Asiatic Bronze. Raw umber for base ; medium chrome yellow
to which add sufficient white lead to suit shade wanted.

Ashes of Roses. Light Tuscan red for base, to which add a
trifle of lamp black.

Autumn Leaf. White lead for base, to which add French
ocher, orange chrome yellow, a trifle of Venetian red, sufficient
to slightly redden tone with more of it, if a deeper-toned red
is desired.

THE PRINCIPAL TINTS 247

Azure Blue. White lead for base ; add Prussian blue to shade
desired of it.

Bay. Lamp black for base; add Venetian red and orange
chrome yellow.

Begonia. Lamp black ; vermilion red of a good scarlet shade,
tinge with Prussian blue.

Bismark Brown. Burnt sienna for base; add burnt umber,
orange chrome yellow. Lighten slightly with white lead to
suit.

Black Slate. Lamp black for base; Prussian blue, slightly
lightened up with white lead. %

Bordeaux Blue. Lamp black for base; orange chrome yellow,
Prussian blue.

Bottle Green. Prussian blue and lamp black for base, and
lemon chrome yellow. To obtain this tint at its best, it should
be glazed over afterwards with a yellow lake.

Brass. White lead for base; add medium chrome yellow;
French ocher to tint wanted.

Bronze Red. Vermilion red for base; orange chrome yellow;
lamp black.

Brown Stone. Tuscan red for base; add orange chrome yel-
low; lamp black; lighten up to suit with white lead.

Brick Color. Yellow ocher for base; add Venetian red to
suit, for very light shades add white lead in very small quantity.

Bronze Green. Extra dark chrome green for base; add lamp
black. This makes a fair bronze green. If extra dark chrome
green is not obtainable, use the dark or even medium chrome
green with more of the lamp black to darken the tint.

Another recipe is given for a richer tone of it ; medium.chrome
green for base; add ivory black and a trifle of raw umber to
shade wanted.

Bronze Yellow. Medium chrome yellow for base; raw umber;
lighten up with white lead.

Browns, all shades and Brown Drabs. Venetian red for base;
add French ocher and lamp black in various proportions accord-
ing to the shade of brown wanted. For the brown drabs add
white lead to the above brown tints, to the desired shade.

Buttercup. White lead for base ; add lemon chrome yellow
to suit.

248 MODERN PIGMENTS

Cambridge Red. Vermilion for base ; add Prussian blue to suit.

Cafe au lait. Burnt umber for base; add white lead; French
ocher; Venetian red.

Carnation. English vermilion for base; add some good
madder lake or carmine. If desired very light, add some zinc
white.

Cerulean Blue. Zinc white for base; add ultramarine blue,
but better use cobalt if procurable and genuine.

Cherry Red. Vermilion for base; add burnt sienna;
crimson lake; ultramarine blue.

Chamois. White lead for base ; add French ocher ; medium
chrome yellow to suit.

Chatnoline. White lead for base; add raw sienna; lemon
chrome yellow to suit.

Chartreuse. White lead for base; add medium chrome
yellow; medium chrome green.

Chestnut. Venetian red for base; add medium chrome
yellow; French ocher and lamp black.

t/ Chocolate. Burnt amber for base; add some rich crimson
vermilion or madder lake.

Another way is French ocher for base; add lamp black and
a little Venetian red to suit.

Canary. Use the chrome yellow sold under that name.
Another way is to take lemon chrome yellow to which add
zinc white to reduce to tint wanted.

Claybank. French ocher for base; add orange chrome
yellow; lighten up to shade wanted with white lead.

Claret. Madder lake and ultramarine blue for base, to which
add some English vermilion and ivory black.

Clay Drab. White lead for base; medium chrome yellow;
raw and burnt sienna.

Cinnamon. White lead for base; add burnt sienna; French
ocher; medium chrome yellow.

\J Cobalt Blue. This is a solid blue. Use blue sold under that
name. If not obtainable, take good ultramarine blue for base,
to which add sufficient zinc white to lighten it to shade required.

Coral Pink. Vermilion for base ; white lead ; medium chrome
yellow.

THE PRINCIPAL TINTS 249

Colonial Yellow. White lead for base; add medium chrome
yellow; orange chrome yellow to tinge it

Cocoanut Brown. Burnt umber for base; lighten up with
white lead.

Cotrine. White lead for base; add orange chrome yellow and
lamp black.

Cream Color, and all the buffs. White lead for base; add some
good French or Oxford ocher to tint wanted ; this will make all
the cream and buff tints from very light to very dark by adding
more or less of the ocher.

Copper. Medium chrome yellow for base; add Venetian red
and a little of lamp black.

Citron. Venetian red for base; add medium chrome yellow
with some Prussian blue just to tinge. If too dark, lighten up
with white lead.

Crimson. Dark English vermilion or any of the dark shades
of vermilion reds. If desired very rich toned, add some good
madder lake or carmine.

Dove Color. White lead for base; add ultramarine blue;
Indian red and lamp black.

Dregs of Wine. Dark Tuscan red for base; lamp black and
a trifle of zinc white.

Electric Blue. Ultramarine blue for base; add white lead
and raw sienna.

Ecru. White lead for base ; add French ocher ; burnt sienna ;
lamp black. This tint varies greatly. Its meaning is raw
and is intended to represent the color of raw flax, before it is
bleached.

Emerald. Paris green as it is or an imitation of it made from
a very pale chrome green of a bluish cast or slightly tinged with
Prussian blue.

Egyptian Green. White lead for base; add raw umber; lemon
chrome yellow; Prussian blue to suit.

Fawn. White lead for base; add medium chrome yellow;
Venetian red; burnt umber.

Flesh Color. White lead for base; add medium chrome yel-
low; French ocher; and Venetian red.

250 MODERN PIGMENTS

French Gray. White lead for base; add ivory black with a
faint tinge of ultramarine blue and madder lake or carmine.

French Red. Indian red for base; add English vermilion to
brighten it, then glaze with madder lake or carmine.

Gazelle. French ocher for base ; add dark Tuscan red ; Vene-
tian red; lamp black; lighten up with white lead.

Geranium. Vermilion red for base; add Indian red and
lamp black.

Gobelin Blue. Ivory black for base ; a.dd white lead ; Prussian
blue; medium chrome green.

Gold. White lead for base ; add medium chrome yellow ; some
good French ocher; and a very little vermilion red or English.

Golden Brown. French ocher for base; add orange chrome
yellow; lamp black; lighten up with white lead to suit.

Gray Green. White lead for base; add ultramarine blue;
lemon chrome yellow; lamp black.

Grass Green. Extra light chrome green just as it comes from
the can. For an extra fine job glaze with Paris green.

Green Stone. White lead for base ; add medium chrome green ;
raw umber, and French ocher.

Gray Stone. White lead for base; add lamp black; Prussian
blue; Venetian red.

Gray Drabs. All shades of them. White lead for base ; add
lamp black or ivory black with a little burnt umber in various
proportion according as a light or deep shade of drab is desired.

Greys. Light ' to dark shades. White lead for base ; lamp
black in various proportions to suit shade wanted.

Hay Color. White lead for base; add orange chrome yellow;
light chrome green; Indian red.

Heliotrope. Zinc white for base; add bright Venetian red;
ultramarine blue.

Indian Pink. White lead for base ; add Indian red.

Indian Brown. Indian red for base; add lamp black; French
ocher.

Iron Gray. Lamp black for base; add white lead and a trifle
of orange chrome yellow.

THE PRINCIPAL TINTS 251

Ivy Green. French ocher for base; add lamp black; Prussian
blue.

Jasper. Lamp black for base ; add white lead ; medium chrome
yellow; light Indian red.

Jonquil. White lead for base; add medium chrome yellow
to which should be added a tinge of red with English pale ver-
milion to enrich it.

Lavender. White lead for base ; add ivory black ; ultramarine
blue; tinge with carmine or madder lake.

Lead Color. White lead for base ; add lamp black and a trifle
of Prussian blue. The latter can be omitted, if the lamp black
is good.

Leather. French ocher for a base; add burnt umber. If a
warm tone of it is desired, add some Venetian red.

Lemon. Use lemon chrome yellow just as it is.

Leaf Buds. White lead for base; add orange chrome yellow;
light chrome green.

Lilac. White lead for base; add dark Indian red to suit.

London Smoke. Yellow ocher for base ; add ultramarine blue ;
lamp black; lighten up to suit with white lead.

Magenta. Vermilion for a base; add carmine or madder lake
with a tinge of ultramarine blue.

Mauve. Yellow ocher for base; add Venetian red; lamp
black; lighten up to suit with white lead.

Mastic. White lead base; add French ocher; Venetian red,
a trifle of lamp black.

Maroon. Carmine or madder lake for base; add ivory black
and a small part of ' orange chrome yellow — another way ;
Tuscan red for base; add orange chrome yellow with a trifle of
ivory black.

Manila or Deck Paint. White lead for base; French ocher;
medium chrome yellow.

Marigold. Medium chrome yellow for base; add white lead;
orange chrome yellow.

Mexican Red. Bright Venetian red for base; red lead.

Mignonette. Medium chrome green for base; add Prussian
blue; medium chrome yellow; lamp black.

252 MODERN PIGMENTS

Moorish Red. Vermilion red for base; add rose pink or,
what is much better, madder lake.

Mouse Color. White lead for base; add lamp black, a tinge
of Venetian red and burnt umber.

Moss Rose. Lemon chrome yellow for base; add medium
chrome green; lighten with white lead to suit.

Mulberry. Ivory black for base; add vermilion red; trifle
Prussian blue.

Myrtle Green. Dark chrome green for base; add ultramarine
blue; lighten up with white lead to suit.

Nile Blue. White lead for base; add Prussian blue; with a
trifle of medium chrome green.

Normandy Blue. Medium chrome green; ultramarine blue; a
trifle of white lead.

Nut Brown. Lamp black for base ; add Venetian red ; medium
chrome yellow; French ocher.

Oak Color. Light and dark shades of it. White lead for
base ; add French ocher ; also a small quantity of Venetian red.
Vary the quantities to suit for light or dark shades.

Old Gold. White lead for base; add medium chrome yellow;
French ocher and a small portion of burnt umber.

Olive. Lemon chrome yellow for base ; add about equal parts
of Prussian blue and lamp black. Some shades of olive can be
made by substituting French ocher for the lemon yellow; in
such a case the tone will not be so bright. A trifle of the lemon
chrome yellow added to the ocher will improve it and make
still another variety of olive tones.

Orange. Orange chrome yellow, just as it comes from the
can. If not to be had, take medium chrome yellow and color
it up with a bright scarlet red — any scarlet-toned vermilion
will do.

Olive Brown. Raw umber for base ; add lemon chrome yellow.
Vary the quantity to suit the intensity of shade wanted.

Orange Brown. Orange chrome yellow for base; add raw
sienna; a trifle of burnt umber.

Oriental Green. Raw umber for base; add lemon chrome
yellow to suit.

THE PRINCIPAL TINTS 253

Opal Gray. White lead for base; add burnt sienna; ultra-
marine blue.

Peach Blossom. White lead for base; add pale Indian red to
suit. A tinge of madder lake will enrich it, but is not a
necessity.

Pearl. White lead for base; add ivory black and a trifle of
ultramarine blue and carmine red. It is a very light shade,
just off the white; do not overdo it.

Pea Green. White lead for base; add medium chrome green

to suit.

Peacock Blue. Ultramarine blue for base; add extra light
chrome green and zinc white to suit.

Persian Orange. Orange chrome yellow for base; add French
ocher; white lead.

Pink. Zinc white for base; add madder lake or carmine or
the crimson shades of English vermilion.

Pompeian Red. Vermilion red base; add orange chrome
yellow; ivory black.

Pompeian Blue. White lead base; add ultramarine blue;
vermilion red; French ocher.

Plum Color. White lead for base; add Indian red; ultra-
marine blue.

Portland Stone. French ocher for base; add raw umber;
lighten up with white lead.

Pistache. Ivory black for base; add French ocher; medium
chrome green.

Purple. White lead for base; add dark Indian red; a trifle of
light Indian red to suit.

Primrose. White lead for base ; add lemon or medium chrome
yellow, according to the shade wanted of it.

Purple Brown. Dark Indian red for base; add ultramarine
blue ; a trifle of lamp black and white lead to lighten it up.

Quaker Green. White lead for base; add French ocher; lamp
black and burnt sienna.

Roan. Lamp black for base; add Venetian red; Prussian
blue ; lighten it up to suit with white lead.

254 MODERN PIGMENTS

Robin's Egg Blue. White lead for base; add ultramarine
blue until the shade is a pretty deep blue, then add some pale
or medium chrome green to suit tone desired of it.

Russet. White lead for base; add orange chrome yellow; a
trifle of lamp black.

Russian Gray. White lead for base; add ultramarine blue;
pale Indian red and lamp black.

Sage Green. White lead for base; add medium chrome green
until the tint is nearly but not quite a pea green, then add lamp
black to bring it to the sage color.

Salmon. White lead for base ; add French ocher ; burnt sienna ;
with a trifle of English vermilion or a good vermilion red.

Sapphire Blue. Zinc white for base; add ultramarine blue.

Sap Green. White lead base; add medium chrome yellow;
lamp black.

Sea Green. White lead base; add Prussian blue; raw sienna.

Seal Brown. Burnt umber for base; add good French ocher
and a trifle of white lead.

Scarlet. Pale English vermilion or any of the scarlet-toned
vermilion reds.

Shrimp Pink. White lead for base ; add Venetian red ; burnt
sienna and a trifle of vermilion.

Sky Blue. White lead for base; add Prussian blue to shade
wanted.

Slate. White lead for base ; add raw umber ; ultramarine blue ;
lamp black.

Spruce Yellow. French ocher for base; add Venetian red;
lighten up with white lead to suit.

Snuff Color. French ocher for base; add burnt umber and a
bit of Venetian red.

Straw Color. Medium chrome yellow for base; add French
ocher; a bit of Venetian red; lighten up with white lead.

Stone Color and Yellow Drabs. White lead for base; add
French ocher; tinge up with medium chrome yellow and burnt
umber. By varying quantities all shades of yellow drabs can
be made.

Tan. White lead for base; add burnt sienna and a trifle of
lamp black.

THE PRINCIPAL TINTS 255

Tally-Ho. White lead for base ; add French ocher ; Venetian
red ; dark chrome green with a bit of ivory black.

Terra Cotta. French ocher for base; add Venetian red and
white lead. Some shades of it require the addition of Indian
red. Some rich shades are sometimes desired under that name ;
use orange chrome yellow in place of French ocher, add Vene-
tian red and a trifle of burnt umber to suit.

Turquoise Blue. White lead for base, or better, zinc white;
add cobalt blue ; Paris green or pale chrome green.

Vienna Brown. Burnt umber for base; add Venetian red;
French ocher; and lighten with white lead to suit.

Violet. White lead for base; add pale Indian red, and a
trifle of dark Indian red.

Willow Green. White lead for base; add sufficient medium
chrome yellow to make a pretty deep shade; then add a small
quantity of raw umber and ivory black.

Wine Color. English vermilion or scarlet-toned vermilion
red for base; add madder lake or carmine; ultramarine blue;
ivory black.

Another way; dark Tuscan red of good quality to which add
a trifle of ivory black.

Water Green. White lead for base; add raw sienna; dark
chrome green.

Yellow Bronze. Lemon or medium chrome yellow for base;
add French ocher and just a trifle of burnt umber.

INDEX

A.

Acacia, 246.
Acorn brown, 246.
Adulterants of white lead, 25.
Adulteration of chrome yellow,
Alabaster, 246.
Alderney brown, 246.
Alizarin, 120.
Aluminous ocher, 58.
Amaranth, 246.
Amber brown, 246.
American ochers, 70, 183.
American sienna, 187.
American umber, 187.
American vermilion, 104, 184.
American zinc, 25.
Analysis of Oxford ocher, 65.
Analysis of terre verte, 140.
Analysis of umber, 162.
Anemone, 246.
Antique bronze, 246.
Antwerp blue, 187.
Apple green, 246.
Apricot, 246.
Armenian red, 246.
Artificial ocher, 183.
Ash gray, 246.
Ashes of roses, 246.
Asiatic bronze, 246.
Aureolin, 87, 183.

properties of, 87.
Aurora yellow, 184.
Autumn leaves, 246.

Azure blue, 247.
Azurite, 187.

B.

Barium chromate, 183.
Baryta lemon yellow, 78, 183.

properties of, 78.
Baryta white, 51, 183.

composition of, 51.

properties of, 52.

source of supply of, 51.

uses as an adulterant, 53.
Baryta white artificially made,
54.

as a distemper color, 55.
Baryta yellow, 183.
Barytes, 183.

Base (the) in mixing tints, 237.
Basic copper acetate, 145, 186.
Bay, 247.
Beeswax, 217.
Begonia, 247.
Benzine, 208.

properties of, 208.

uses of, 209.
Berg blau, 187. '
Berg grim, 186.
Berlin blue, 187.
Best vehicle for white lead, 22.
Bice, 187.

Bismark brown, 247.
Black lead (see graphite), 188.
Black pigments, 170.
Black pigments, 188.

257

258

INDEX

Black slate, 247.
Blanc d 'argent, 182.
Blanc de plomb, 182.
Blanc de zinc, 182.
Blanc fixe, 183.
Bleu d'azur, 186
Bleu de Berlin, 187.
Bleu de cobalt, 187.
Bleu de smalte, 187.
Bleu de Thenard, 187.
Bleu d'outremer, 186.
Blow pipe test for white lead,
29.

how to make, 30.
Blue black (see charcoal black),

188.

Blue pigments, 186.
Blue smalt, 155.

properties, 155.
Blue verditer, 154, 187.

production of, 154.

properties of, 154.
Boiled linseed oil, 203, 231.

adulterations of, 231.

properties of, 231.

uses of, 231.
Bordeaux blue, 247.
Bottle green, 247.
Brass, 247.
Brick color, 247.
Bronze green, 247.
Bronze red, 247.
Bronze yellow, 247.
Brown ocher, 183.
Brown pigments, 187.
Brown pink, 184.
Brown stone, 247.
Browns, 247.
Brun de Vandyke, 188.
Burnt ocher, 184.
Burnt, sieriha, 187.
Burnt umber, 159, 187.

properties of, 159.

uses of, 159.
Buttercup, 247.

Cadmium, 92.

chemistry of, 92.

properties of, 92.
Cadmium gelb, 184.
Cadmium yellow, 184.
Cafe au lait, 248.
Cambridge red, 248.
Canary, 248.

Caput motuum vitrioli, 184.
Carbonate of lime (see whiting),

41, 182.

Carbon black (see gas black), 188.
Carmin, 184.
Carmin de garance, 185.
Carmin lack, 185.
Carmine, 127, 185.

history of, 127.

properties of, 127.

uses of, 127.
Carnation, 248.
Cassel earth, 188.
Cendres blues, 187.
Cerulean blue, 187, 248.
Ceruleum, 153, 187.

properties of, 153.

uses of, 153.
Ceruse, 153.

Chalking of white lead, 21.
Chamois, 248.
Chamoline, 248.
Charcoal black, 187, 188.

preparation of, 178.

properties of, 178.

uses of, 178.
Chartreuse, 248.
Cherry red, 248.
Chessylite, 154, 187.
Chestnut, 248.

China clay (see kaolin), 183.
Chinese blue, 150, 186.

properties of, 150.

uses of, 150.
Chinese vermilion, 184.
Chinese white, 182.

INDEX

259

Chocolate, 248.

Chromate of lead, 183, 184.

Chrome, 183.

Chrome green, 129, 185.

chemistry of, 129.

manufacture of, 130.

properties of, 132.

proprietary names for, 131.

uses of, 133.
Chrome jaune, 183.
Chrome yellows, 73, 183.

chemistry of, 74.

general remarks on, 73.

manufacture of, 74.

medium, 74.

properties of, 74.

canary and lemon, 75, 183.
manufacture of, 75.

orange, 75, 183.
defects of, 77.
manufacture of, 75, 183.
properties of, 76.
uses of, 77.
Chrom gelb, 183.
Chromium sesquioxide, 186.
Cinnabar, 184.
Cinnamon, 248.
Citrine lake, 184.
Citron, 249.
Claret, 248.
Clay bank, 248.
Clay drab, 248.
Cobalt blue, 248.
Cobalt blue, 152, 187.

manufacture of, 152.

properties of, 152.

uses of, 152.
Cobalt green, 135, 185.

properties of, 135.

uses of, 135.

Cobalt yellow, (see aureolin), 183.
Cocoanut brown, 249.
Coelin, 187.
Coelin blue, 187.
Colcothar, 184.

Collen earth, 188.

Cologne earth, 188.

Colonial yellow, 249.

Coloring pigments for tints, 235.

Compounding of pigments, 187.

Copper, 249.

Coral pink, 248.

Cotrine, 249.

Cream color, 249.

Cremser weiss, 182.

Crimson, 249.

Crocus, 184.

Cupric arsenite, 186.

Cyprus umber, 187.

D.

Dahl process white lead, 27.

manufacture of, 28.

properties of, 28.
Dark chrome green, 185.
Dextrin, 226.

properties of, 226.
Dove color, 249.
Dregs of wine, 249.
Drop black (see ivory black),

175, 188.
Dryers, 229.

general remarks on, 229.

lead oxides as driers, 232.

oxides of manganese, 232.

paste form, 233.
Dumont's blue, 187.
Dunkel gelb lack, 184.
Dutch pink, 90, 184.

character of, 90.

properties of, 91.
Dutch process white lead, 9.

chemistry of, 11.

corroding of, 10.

E.

Earth whites, 40.
general remarks, 40.

260

INDEX

Ecru, 249.

Egyptian green, 249.

Electric blue, 249.

Elfenbein schwartz, 188.

Emerald, 249.

Emerald green (see Paris green),

143.
Emerald oxide of chromium,

186.

English ochers, 69.
English umber, 187.
English vermilion (see vermilion),

184.
Extra light chrome green, 185.

F.

Fawn, 249.
Fixed oils, 189.
Flake white, 22, 182.
Flaxseed oil (see linseed oil), 189.
Flesh color, 249.
Floated barytes, 183.
Frankfort black, 188.
Frankfurter schwartz, 188.
French blue, 186.
French gray, 250.
French ocher, 183.
French red, 250.
French zinc, 34.

G.

Gamboge, 86, 183.

properties of, 86.
Gas black, 173, 188.

properties of, 173.

uses of, 174.
Gazelle, 250.
Gelben ocher, 183.
Geranium, 250.
Giallo di napoli, 186.
Glues, 220.

general remarks on, 220.

properties of, 221.

uses of, 222.

Glycerine, 228.

properties of, 228.

uses of, 228.
Gmelin's blue, 1S6.
Gobelin blue, 250.
Gold, 250.
Golden brown, 250.
Gommegutte, 183.
Graphite, 179, 188.

production of, 179.

properties of, 180.
Grass green, 250.
Gray drabs, 250.
Gray green, 250.
Gray stone, 250.
Green bice, 186.

Green carbonate of copper, 186
Green earth, 186.

Green oxide of chromium, 134,
186.

properties of, 134.

uses of, 134.

Green pigments, 129, 185.
Green stone, 250.
Green verditer, 142, 186.

properties of, 142.
Greys, 250.

Grinding colors, a trade, 68.
Griin erde, 186.
Grimes chromoxyd, 186.
Griins pan, 186.
Guimet's blue, 186.
Gum arabic, 224.

properties of, 224.

uses of, 225.
Gypsum, 46, 183.

chemistry of, 47.

history of, 46.

properties of, 47.

source of supply, 46.

H.

Hay color, 250.
Heavy spar, 183.

INDEX

261

Heliotrope, 250.
History of white lead, 9.
Honey, 227.

properties of, 227.

I.

Imitation vermilion, 100, 184.
Impurities in linseed oil, 201.

properties of, 126.

tests for, 201.

uses of, 126.
Indian brown, 250.
Indian lake, 126, 185.
Indian pink, 250.
Indian reds, 110.

characteristics of, 110.

production of, 110.

properties of, 112.

uses of, 112.
Indian yellow, 87, 183.

chemistry of, 88.

properties of, 88.
Indisch gelb, 183.
Iron gray, 250.
Italian pink, 1$4.
Italian sienna, 187.
Ivory black, 175, 188.

manufacture of, 175.

properties of, 176.

uses of, 176.
Ivy green, 251.

.1.
Japans, 214.

properties of, 214.

uses of, 214.
Jasper, 251.
Jaune brilliant, 184.
Jaurie d'antimoine, 184.
Jaune de cadmium, 184.
Jaune de cobalt, 183.
Jaune de Mars, 183.
Jaune de Naples, 184.
Jaune Indien, 183.
Jaune royal, 184.
Jonquil, 251.

K.

Kaolin, 44, 183.

properties of, 45.
King's yellow, 93, 184.

characteristics of, 93.

chemistry of, 94.
Kobalt blau, 187.
Kobalt gelb, 183.
Kobalt griin, 185.
Konig's gelb, 184.
Krapp lack, 185.

L.

Lac lake, 185.
Lack lack, 185.
Lakes, 118.

general remarks on, 118.

manufacture of, 121.

red lakes, 119.
Lamp black, 170.

chemistry of, 170.

manufacture of, 170.

properties of, 171.

uses of, 172.
Lapis lazuli blau, 186.
Laque brown, 183.
Laque cramoisi, 185.
Laque de garance, 185.
Laque d'Inde, 185.
Lavender, 251.
Lazurestein blau, 186.
Lead color, 251.
Lead (sulphate), see sulphate of

lead, 26.
Lead (sublimed), see sublimed

lead, 27.

Lead (white), see white lead, 9.
Lead (white oxide), see white oxide

of lead, 28.
Leaf buds, 251.
Leather, 251.
Lemon, 251.
Levant umber, 187.
Lilac, 251.

262

INDEX

Linseed oil, 191.

boiled, 203.

chemistry of, 195.

drying of, 196.

manufacture of, 191.

properties of, 198.

tests for impurities, 201.

uses of, 199.
Liquid dryers, 231.

general remarks on, 231.
List of principal tints, 243.
London smoke, 251.

M.

Madder brown, 185.
Madder lakes, 123, 185.

properties of, 124.

uses of, 124.
Madder purple, 185.
Madder red, 185.
Magenta, 251.
Malachite, 142.
Manilla or deck paint, 251.
Marigold, 251.
Maroon, 251.
Mars gelb, 183.
Mars orange, 183.
Mars yellow, 183.
Mastic, 251.
Mauve, 251.

Medium chrome green, 185.
Medium chrome yellow, 183.
Metallic browns, 166.

manufacture of, 166.

properties of, 167.

uses of, 167.
Mexican red, 251.
Mignonette, 251.
Miltos, 185.
Mineral yellow, 183.
Mittes green, 186.
Mittler's green, 186.
Mixing compound tints, 239.

general remarks on, 243.

how to prepare, 240.

Mixing compound tints — cont'd.

in distemper, 241 .
Mixing simple tints, 239.
Molasses (see honey), 227.
Moorish red, 252.
Mortar colors made from ochers,

75.

Moss color, 252.
Mouse color, 252.
Mountain blue, 187.
Mountain green, 186.
Mulberry, 252.
Myrtle green, 252.

N.

Naphtha (see benzine), 208.
Naples yellow, 89, 184.

chemistry of, 89.

history of, 89.

properties of, 89.
Neapel gelb, 89.
Neutral tints, 236.
New blue, 186.
Nile blue, 252.
Noirr de fumee, 188.
Noir d'ivoire, 188.
Noir de vigne, 188.
Normandy blue, 252.
Nut brown, 252.

O.

Oak color, 252.
Ocher jaune, 183.
Ocher roth, 185.
Ocher rouge, 185.
Ochers, 57, 183.

aluminous, 59.

analysis of Oxford, 65.

chemical properties, 58.

general characteristics, 58.

grinding in oil, 67.

mining of, 61.

properties of, 61.

silicate, 58.

uses of, 63.
Oil of turpentine, 207.

INDEX

263

Old gold, 252.

Olive, 252.

Olive brown, 252.

Opal gray, 253.

Opa,que oxide of chromium, 186.

Orange. 252.

Orange brown, 252.

Orange cadmium, 184.

Orange chrome yellow, 183,

Orient yellow, 184.

Oriental green, 252.

Orpiment (see king's yellow), 184.

Oxford ocher, 183.

Oxide of zinc (see zinc white), 182.

P.

Paraffin waxes, 219.

characteristics of, 219.
Pariser blau, 187.
Paris green, 143.

chemistry of, 143.

preparation of, 143.

uses of, 143.
Paris white, 182.
Peach blossom, 253.
Peacock blue, 253.
Pea green, 253.
Pearl, 253.
Peori, 183.

Permanent blue, 186.
Permanent weiss, 183.
Permanent white, 183.
Permanent yellow, 183.
Persian orange, 253.
Pigment, definition of, 2.
Pink, 253.

Pink madder lake, 185.
Pistache, 253.
Plumbago, 188.
Plum color, 253.
Pompeian red, 253.
Poppyseed oil, 204.

properties of, 204.

uses of, 204.
Portland stone, 253.

Powdered silica, 183,
Preface, iii.

Preliminary remarks, i.
Primary colors, 235.
Primrose, 253.
Prussian blue, 148, 187.

Listory of, 148.

manufacture of, 148.

properties of, 149.

uses of, 149.
Prussiate of iron, 187.
Puiri, 183.

Pulp ground white lead, 16.
Puree, 183.
Purple, 253.
Purple brown, 253.
Purple lake, 185.
Purpurin, 120.

Q-

Quaker green, 253.
Quercitron lake, 184.

R.

Raw sienna, 163, 187.
Raw umber, 156, 187.
Red chalk, 185.
Red hematite, 185.
Red iron ore, 185.
Red lead, 116.

chemistry of, 116.

history of, 116.

properties of, 117.

uses of, 117.
Red ocher, 185.
Red oxide of iron, 114.

properties of, 114.

uses of, 115.
Red pigments, 95.
Rinkman's green, 185.
Roan, 253.

Robin's egg blue, 254.
Roman ocher, 185.
Rose lake, 123.

properties of, 123.

uses of, 123.

264

INDEX

Rose madder lake, 185.
Rose pink, 122.

properties of, 122.

uses of, 122.
Rouge, 184.
Rouge de Venise, 184.
Royal blue, 155, 187.
Ruben's madder, 185.
Rubrica, 185.
Ruddle, 185.
Russ, 188.
Russet, 254.
Russian gray, 254.

S.

Sage green, 254.

Salmon, 254.

Sap green, 254.

Sapphire blue, 254.

Saxon blue, 187.

Scale test for adulterations :

how to make it, 81.

in colors, 80.
Scarlet, 254.
Scarlet ocher, 185.
Scheele's green, 144, 186.

characteristics of, 144.
Scheele's griin, 186.
Sea green, 254.
Seal brown, 254.
Secondary colors, 235.
Shellac (alcoholic solution), 215.

properties of, 215.

uses of, 215.
Shrimp pink, 254.
Siccatives (see driers), 229.
Sienna erde, 187.
Siennas, 161, 187.

analysis of, 162.

burnt sienna, 163.
properties of, 164.
uses of, 164.

chemistry of, 162.

general characteristics, 161.

history of, 161.

Siennas — continued.

properties of, 163.

raw sienna, 163.
properties of, 163.
uses of, 163.
Silicate earth, 48.

chemistry of, 49.

properties of, 49.
Silver white, 182.
Silver white, 183.
Sky blue, 254.
Slate, 254.
Smalt, 187.
Smalte, 187.
Snuff color, 254.
Soluble blue (see Chinese blue),

150, 186.
Spanish brown, 168.

properties of, 168.

uses of, 168.
Spanish white, 182.
Spirits of turpentine, 207.

manufacture of, 207,
Starch, 226.

properties of, 226.
Stone color, 254.
Straw color, 254.
Strictly pure vs. compound leads,.

24.
Sublimed lead, 27.

properties of, 27.
Sugar (see honey), 227.
Sulphate of barium, 183.
Sulphate of lead, 20.

chemistry of, 26.

properties of, 26.
Sulphate of lime (see whiting),

182.

Sulphide of cadmium, 184.
System of packing white lead, 23.

T.

Table of synonyms, 181.
Tally-ho, 255.
Tan, 254.

INDEX

265

Terra-cotta, 255.
Terra di sienna, 187.
Terra ombra, 187.
Terra rosa, 187.
Terra verde, 186.
Terre d 'ombre, 187.
Terre de sienne, 187.
Terre de verone, 186.
Terre verte, 139, 186.

analysis of, 139.

history of, 139.

production of, 139.

uses of, 139.
Tertiary colors, 236.
Turkey umber, 156, 187.
Turner's blue, 187.
Turquoise blue, 255.
Tuscan reds, 112.

manufacture of, 112.

properties of, 113.

uses of, 113.

U.

Ultramarine blue, 145, 186.
chemistry of, 145.
manufacture of, 145.
properties of, 146.
uses of, 146.
Umbers, 156, 187.
burnt umber, 159.

properties of, 159.
chemistry of, 157.
properties of, 158.
provenances of, 156.
raw umber, 156.
burnt umber, 159.
properties .of, 156.
uses of, 158.
Umbraun, 187.

V.

Vandyke brown, 165, 188.
properties of, 165.
provenance of, 165.

Vandyke brown — continued.

uses of, 165.
Varnishes, 210.

general remarks, 210.

properties of, 211.

uses of, 212.
Vegetable waxes, 217.

characteristics of, 217.
Vehicles for mixing pigments, 189.
Venetian red, 106, 184.

history of, 106.

manufacture of, 107.

properties of, 109.

uses of, 109.
Verdigris, 141, 188.

chemistry of, 141.

properties of, 141.

uses of, 141.
Vermilion, 95, 184.

characteristics of, 98.

chemistry of, 96.

history of, 95.

source of supply, 95.

uses of, 99.
Vermilion reds, 100, 184.

manufacture of, 101.

properties of, 103.

uses of, 103.
Vert emeraude, 186.
Vert de chrome, 186.
Vert de cobalt, 185.
Vert de gris, 186.
Vert de Guimet, 186.
Vert de Montpelliers, 186.
Vert de Scheele, 186.
Vert de zinc, 185.
Vert Panetier, 186.
Vert Paul Verone, 186.
Vienna brown, 255.
Vine black, 188.
Violet, 255.
Viridian, 137, 186.

properties of 137.

uses of, 137.
Volatile oils, 206.

266

INDEX

w.

Water green, 255.
Waxes, 217.
White lead, 9.

chalking of, 21.

chemistry of, 11.

cylinder system of corrosion, 18.

defects of, 21.

Dutch process of corroding, 10.

grinding dry in oil, 15.

history of, 9.

injurious gases, 22.

manufacture by, 12.

process of manufacture, 19.

properties of, 20.

pulp ground lead, 16.

ripening oil ground lead, 16.

stack system of corrosion, 11.

vehicles for, 22.

volatile oils for, 22.

working qualities, 20.
White oxide of lead, 28.

hardening in package when

ground in oil, 28.
White pigments, 8.
White silicate, 183.
Whiting, 41, 182.

chemistry of, 42.

levigation of, 42.

Whiting — continued.

mining of, 42.

properties of, 43.

qualities of, 43.

source of, 42.
Willow green, 255.
Wine color, 255.

Y.

Yellow bronze, 255.
Yellow lake, 184.
Yellow madder, 184.
Yellow ocher, 57, 183.
Yellow pigments, 57, 73, 183.
Yellow ultramarine, 183.

Z.

Zaffre, 187.
Zinc green, 135, 185.
Zinc Weiss, 182.
Zinc white, 32, 182.

chemistry of, 33.

compounds of, 38.

defects of, 37.

history of, 32.

in distemper, 39.

manufacture of, 33.

properties of, 36.

tests for purity of, 35.
Zunzober, 184.

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